Xbox one X easily powerful enough to hand 60fps.
Choices made to improve graphics on top of 4k instead.
New Forza being developed using The X as the primary console.
4x MSAA still used on top of 4k
New development tools (which they had early access) really good
4k same settings as original = 25% spare GPU
Motion blur same as PC
Car detail a lot higher than original
Distance viewing better than original
Custom setup between ultra and high
Somethings higher than PC can get such as shadow resolution (4k)
Reflections much higher quality
Easy and quick transition
Still head room for future.
Please note this is not me saying any of this but a developer of the game.
If they could do 60fps they should have offered it really in my view.