this problem persists in all versions 1.20 and 1.20.1 official and 1.20.20 beta/preview.
Including @GoldenHelmet, my friends who also play this version report the same problem described with the observer blocks.
Yes, this problem is happening in all worlds created by me in this version.
this problem persists in all versions 1.20 and 1.20.1 official and 1.20.20 beta/preview.