As a driver developer, I've been on the receiving end of stuff breaking due to changes in macOS many a time. Based on my experience, I find it much more likely

As a driver developer, I've been on the receiving end of stuff breaking due to changes in macOS many a time. Based on my experience, I find it much more likely that Apple simply does not care about this problem/does not consider it a problem. By that I mean they are not willing to assign developer resources to the situation because from their point of view it is not a supported configuration, plain and simple. The fact that it ever worked is largely accidental as far as they are concerned. One of their highest priorities at the moment appears to be to remove any 3rd party code running in the context of Apple processes. For examples, you don't need to look far: kext -> DriverKit/System Extension transition, hardened runtime, etc. The Nvidia driver breaking is just a consequence of that increasing lockdown. The simplest solution would be to allow nvidia's code to run in the context of core system and user processes again (kernel, WindowServer, just about any GUI app) which presumably is not palatable to them or they wouldn't have made the change in the first place. The alternative would be to farm this type of driver out into a sandboxed user process. (Nowadays this means DriverKit.) Aside from potential performance issues, this would be a lot of work, so it's probably never going to happen unless literally millions of end users start complaining.