Why won't the M1 and M2 iPad Pros be compatible? Are you saying because they don't have 16GB of RAM (because they do if you got a 1TB or 2TB model)?Maybe they should have made 16GB of RAM the base memory on the M4 iPP. Other than that, I don’t really see the need of a hardware upgrade, as the M4 chip is really a beast, as the M4 Mac lineup has shown.
If they keep launching new iPad Pros every year, whenever they decide to release a more desktop oriented iPadOS, it won’t be compatible with the M1 & M2 iPP, and that will piss many of us off, because those iPad Pro are really capable machines.