I think my performance post came across a little bit misunderstood. In no way it is acting like a non-accelerated Mac, but it is noticeably *slower* than Catalina when running animations, especially with Safari.
So I just compared Catalina and Big Sur beta 6 on my Late 2012 13" Retina MBP. Dock icons bounce a little more smoothly in Catalina when programs are loading. Otherwise, everything seems just a little smoother and faster to me in Big Sur,
especially Safari. (Yes, I installed Safari 14 under Catalina before making this comparison.) And I have the transparent menu bar in both Catalina and Big Sur -- it's clear that both are getting accelerated.
(I did cheat a little by using dd on Linux to copy my Early 2011 13" MBP's internal SSD contents onto an external SSD. Both SSDs are the exact same capacity, exact same number of sectors, which made that the easy way to go. However, I don't think it's likely that this would make any difference, and I can double-check later by going through the whole installation procedure on the Late 2012 when I get a chance.)
MrWeenus, would you mind doing the following? Go to the Apple menu, choose About This Mac, choose System Report, and on the left side, under Hardware, click "Graphcis/Displays". (It may look like "Graphics/Dis.." or something like that, depending on the window size.) Then take a screenshot of the window. (A screenshot of the whole screen, so we can see the menu bar as well, probably would be even better.) And post the screenshot to this thread. Thanks!