For missing the FOV option, most of the time it's some boneheaded decision to keep the console and PC games identical, as the console versions are optimized to handle exactly the amount of stuff that could be on the screen at once with the default FOV. There really is no real reason not to add it in the PC version - quite a few games do have a disclaimer akin to "If you increase the FOV, you might see graphical glitches", but that's fine.
As for the super ultrawide there is an actual obstacle, the UI. You often can't use the same one as you either have them horribly stretched, sitting in the middle blocking your view or spread uselessly all the way at the edges. So someone has to actually do some work to make it work.

As an example, here's Starfield super ultrawide comparison between the default FOV and 120 degree FOV. You can imagine the performance cost and possible visual glitches you might get from doing that.