I sincerely hope the two recent FAA caused scrubs were not politically motivated; a new administration's veiled support of K-Street, putting the 'new kid on the block' on notice. Maybe the 'big-guy' wants some kick-back? The Greenies are already working to shut the ship-yard down.
The Verge reporting on this is: the SN8 flight violated the FAA-approved flight parameters in some way. This isn't completely shocking given that it flew a dramatically different flight profile than was expected (outside SpaceX) before the launch. The violation triggered an investigation, as well as extra scrutiny for the SN9 flight. It seems that extra scrutiny is delaying the launch, with the Raptor swap possibly specific sticking point at this time.
It should be noted the FAA could have been putting out press releases blasting SpaceX for the violation or for seeming to play chicken with the launch approval process this past week, but is remaining quite reserved with their statements. The agency may be holding them up, and we may disagree with the decisions which have lead to this situation, but they don't appear to be doing it for any nefarious reasons. As Elon himself has indicated, this is a fast-moving project running into a regulatory environment that's not suited to it, becuase the regulations and the office were designed for conventional expendable vehicles developed in more conservative programs.
None of that is unusual or conspiratorial, and most of it predates the current administration. If you want to be mad at politicians be my guest, but note that the most powerful guardian of SLS is still the senior senator from Alabama, and the current head of the FAA took office in August of 2019.