I have a new iMac 27" 2020 and just learned, to my disappointment, that my graphics card is not supported. I have an AMD Radeon Pro 5700, I think the standard for the new iMac is a Radeon Pro 5500 XT (which is also not supported).
This causes Illustrator to crash at least once or twice a day with a GPU Error report and it then automatically deactivates GPU Performance, which makes Illustrator super slow and laggy.
I know the iMac 2020 is very new, but since more people will be getting it over time it seems reasonable to support those graphic cards.
Thanks.