I had the android 11 beta on my Samsung s20 ultra and downgraded it back to android 10, too many bugs and really there wasn't any thing different, sign up for a beta tester when it comes up and make sure you back up with smart switch pc software as you might want to reverse or downgrade your firmware.
nothing special in android 11, it rolls out nationwide Samsung said 2021 January.
if it ain't broken leave it