Tanks simply haven't done much for decades. The side with tanks don't just beat the side without tanks. How many armored divisions did the taliban have? How did pickups of Chad beat the Libyans? How did the Syrian regime's armor fare against the rebels? How did Isis rout Abrams equipped Iraqis. Turkish and Azerbijan tanks gets exploded when their drones gets kill after kill without resistance. The side with the tanks against an opponent with air superiority just generate highlight reels for the nightly news as it happened pretty much every time.
It is not like the light formations just rolled over and died since the invention of the tank. All the frontline formations held ground and managed local counterattacks, it is only that "armor" that did exploitation.
Do compare and contrast with airpower, where when a side who managed sufficient capability can wage zero casualty wars forever, and just bomb the opponent into submission.
It also appears that the relevant amount of armor for offensive success is resistance to machineguns and artillery, which a pickup with some plates welded can manage with reasonable mobility, after decades of 4WD improvements. It is impossible to persistently overmatch peer opponent anti-armor and not necessary for success, simply destroy the opponent before one run out of forces.
Today motorbikes and golf carts are succeeding in taking the ground where ruins of decades of stockpiled tanks lie on the route.
Tanks is just a gun platform, and there are lot of ways to deliver explosives and there are kinds of substitutes that all have different advantages. Tanks are not stealthy enough, fast enough, nor have good enough sensing to do much other than fires today.
It isn't the era where Rommel can disappear a entire tank division behind the enemy while armies on land line telephones gets all confused.
30+ yrs of finalizing? It’s called “no new threat” and “we just aren’t sure what we want.” This isn’t some plan 30+ yrs in the making that’s been steadily followed.
People wanted the tank to help move infantry to the enemy part of the cover while under fire from machineguns.
The problem is solved with IFVs. IFVs get developed while tanks is defined by an arms race firepower-protection spiral that only relevant amongst itself. Exit the arms race and specialize in something else (more AA, more weapons range, different weapons config, etc), and it stops being a tank by the definition of the word.
Its like how battleships ceased existing, but large surface warships haven't. Exit the gun-armor arms race and fit different systems and it gets defined something else.
I assume you're referring to video games here, because IRL you cannot really "attach" a unit mid-combat. As in, teleport a unit into a combat zone the instant someone spooky appears. You have to send that unit in beforehand, to accompany the maneuvering unit along the way. And of course you scope out the area you assault to get a grasp of what you're going to face.
Ever since assault breaker knows you can spot tanks deep behind enemy lines thanks to the wonders of RADAR, and direct fast moving flying vehicles to the problem before the slowness of tanks becomes a problem.
Today, even ghetto forces can spam drones or other affordable sensors to spot tanks behind the enemy lines, and move anti-tank into position before contact is made. It is not like tanks actually do damage quickly however, and mobile reserves of land vehicles is fast enough to contain situations even without airpower. Consider:
That the German independent TD formations. For combat between countries with some strategic depth: if attacks are possible, it is also valid to retreat and counter attack.
Compare that with dealing with airplanes. Airplanes are both stealthy and fast, so not having sufficient concentration anywhere on the front can mean destruction.
Look I'm gonna be real honest here: I have absolutely no idea what kind of goofy assault force a single VSHORAD vehicle is. What's it trying to do? Force recon?
Where I said a single vehicle? It is more like you take a standard combine arms formation, and pick vehicles to delete because it is inefficient to have too many specialized vehicles: The lesson of the MBT over the mess that was interwar tank specialization showed that.
So: MBT, VSHORAD, Other AA, IFV/APC, Engineering, Artillery
Delete VSHORAD, drones kills you. Delete long range AA and classic air power kills you. Delete IFV/APC infantry get deleted by artillery. Delete Engineering, you get stuck. Delete artillery, the formation can't concentrate fire.
If you delete MBT from the formation while giving other random vehicles high performance AT-missiles, the formation would still work. The artillery can even conduct direct fire on structures as long as it is small arms protected and CRAM coverage is available.
APS is actually dirt cheap. You should familiarize with the topic. Tanks without SHORAD can actually survive quite well, and we have recent wars to demonstrate that.
C-RAM can be deployed by simply putting C-RAM on an offroad truck with a smaller independent radar.
Starstreak is also a large system, while an APS is a very compact system with streamlined integration.
Tanks without air defense get exploded in recent wars if opponent have air power, and with drones, everyone have airpower.
All vehicles without armor can get destroyed by classical artillery. Given that defensive system accuracy is not remotely perfect, C-RAM can't outshoot cluster artillery.
Without SHORAD, even if the opponent don't have a big EFP to pen top armor, drones can still pick off the radar and burn defensive charges with everything from classic bombing to gun-armed strafing runs (gun armed interceptors drones is now a thing) to just burn a bunch of FPVs since its dirt cheap anyways. APS radars also don't survive artillery.
Not enough space. Not feasible.
Sprut-SD is not that big or heavy for a full powered gun. Almost all IFV can fit a turret that mount this gun, from CV90120, Lynx 120mm, Centauro II. Sheridan packed 152mm on 15tons. There are a lot of light to medium weight formation that could have this class of weapon equipped, but almost none bother. The Stryker formations even replace 105mm MGS with 30mm Dragoon.
And soft targets, and light armored vehicles, and helicopters, and whatever else dares move in its LoS.
It's funny that you criticize people who over-focus on APFSDS and then you do the exact same thing.
Soft targets get destroyed by autocannons, only another Tank require 120mm. When a IFV that can carry troops can service the same target set, one wonders what is the point.
Trajectory is different between artillery and tanks. In fact, trajectory limitations are exactly why the workshare of artillery is decreasing.
Here's the effect of HE-MP shells in MOUT. You can selectively target just one specific area.
More munitions are inserted to the portfolio as time goes on to give the local commander more options of trajectory, warheads, effect types (e.g. penetration). Removing the premier precise direct fire option does not go well with that.
Just about every weapon can shoot direct, and lots of cheap ones.
Consider UAVs that can fly into windows and conduct search and destroy ops inside structures, direct fire is just clumsy.
Consider UGV that fits high explosive rockets of one's choice, the cost is now on the order of $30k. Every squad can have three instead of the rare heavy formation.
Consider every AFV with direct fire capable gun, it is not like concrete can bounce APHE. A gun mortar vehicle like Nona can be both artillery and do this mission, as well as shoot at rooftops, unlike how the Russians suffer heavy losses in grozny because tank guns don't elevate.
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Of course, structure demolishing do favor specialized vehicles, but no one considers an AVRE or StrumTiger a war winner.