Unfortunately not a whole lot of compatibility at this point.
The list need to be taken into context.
1. Cards where there is no Mac compatibility at all . The M-series not working is not 'new'. ( macOS has had very poor coverage for very high end bandwidth Ethernet cards for basically since they crossed the 25Gb/s mark. . )
2. Some cards are old and their drivers are pragmatically abandoned. They happen to work as long as you don't make major changes to the OS kernel. Apple has deprecated kernel extensions before the transition( so on both Intel and M-series side of macOS lines of development). Those drivers will disappear in the future. So even if M and no 'M1' coverage. Those cards a walking zombies. Those not making the transition should not be all that surprising.
Cards that have DriverKit drivers are not going to be a problem. But there are several folks dragging their feet on transition. Sometimes that is because nobody is asking for it. Some vendors have done stop gap kext drivers for M-series and will transition later. Some card folks are looking to just do it once.
Also older cards where no customers are paying for new driver updates. Again shouldn't be a surprise (no pay , no work).
3. Anything that has to do with providing essential services at the very early boot stage is likely going to have problems. GPUs (so can see the screen). Any kind of software RAID and older storage controller that is not covered in the new Boot startup mechanism ( not booting EFI/UEFI with BIOS fallbacks anymore).
4. Anything with bandwidth needs that far outstrips Thunderbolt is probably on a slow boat.
5. Dump the GPU section. (that is actually a "M-seres ecosystem " policy thing )
That said it would probably help if the line up had a Mac where didn't need to buy an TB external enclosure to drive more card sales. More cards sales leads to more driver development funds which leads to keep the list longer on at least new(er) cards.