Credit where it's due: Playground have finally listened to basically everyone & actually implemented TAA into FH5. Given the level of foliage (where driver-forced transparency supersampling AA was prohibitively expensive & totally absent from the in-game options), this should provide a much more stable image. Bit of a shame it doesn't appear to be FSR2/DLSS2, given they're going in that direction to implement any TAA solution.
https://youtu.be/hyzmFfjzh6I
Wishing FH5's TAA implementation was FSR2 (even if they have zero interest in ever giving me what I really want & doing DLSS). What we get is TAA with CAS sharpening & then a separate upscaler (which is FSR 1.0 so also CAS - hope they don't run it twice when both options are enabled).
It's not terrible, and gets rid of some aliasing their MSAA+MLAA options could not, but it's also definitely not amazing at native res (and right now great TAA means these advanced TAAU options).