Hey, what is your source on that...I am pretty sure the F-22 AND F-35 "coating stacks" are heavily classifiedMany of the basic, regular maintenance tasks on the F-22 require removal and reapplication of coatings. This is labor intensive. The F-22 coatings also degrade due to features of the F-22 design.
"F-35 RAM" is not going to solve these problems.
The F-35 was designed to make access to the inside of the aircraft easier and require less messing with the coatings. That can't be retrofitted to the F-22. The F-35 also has a fundamentally different coating stack because the structure was designed differently.