MacBook Pro (15-inch, 2019)
Same here. Scrolling, typing, selecting menu items, clicking buttons, selecting finder windows - lags like crazy. Often the wheel is spinning for several minutes, sometimes the system appears simply to be frozen.
Ran CleanMyMac, reset SMC, PR Ram. Turned off animations and transparency. The latter seemed to have helped a bit, but still - it is unacceptable.
Even as I type this, the wheel appears, input puffers and mouse movements, clicks and keystrokes seem to be buffered, the fired all at once.
Catalina worked perfectly fine with all graphical enhancements turned on.
t-binder
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