OpenXR toolkit can get dynamic foveated rendering working in ACC, Even if Kunos don't support it officially oxr toolkit should still work in AC2. I'm not real sure what you mean by hw support but oxr toolkit dfr uses vrs for the lower res rendering so I guess technically that could be considered hw support? I wouldn't expect AC2 on the crystal to be heavier than flight sim on an aero anyway, the resolution difference isn't massive 2880 x 2720 per eye for aero vs 2880*2880 for the crystal.
It would be nice if they would just look at what settings people are using the toolkit for (it's mainly foveated rendering in the outter 30% of the fov and sometimes supersampling the middle) and have it built into the game but even in the likely event they don't bother again we have options still.
The foveated rendering extension has decoupled the required rendering resolution based on eye tracking and perceived resolution.