1.18 betas were completely functional on Switch, but updating a pre existing world to 1.18 completely destroys gameplay. Pressure plates don't work, the player crouches uncontrollably, and after dying all mobs and items from the place of death can still interact with the player. The menu is also impossible to open, mobs are impossible to interact with for visiting players, and there are increased chunk loading issues.

I executed this bug by updating a pre-existing world (originally made in 1.16) to 1.18 and a friend entering the world, but some of the issues mentioned were already present before the friend joined.