Several players in my realm including my son are having issues with their switch freezing since the update. 
My son can barely get Minecraft to open without his switch freezing and needing a hard reset. When he does get it open, it freezes again at least half of the times he tries to sign into a realm. 
Two other realm member who play on the switch are experiencing the same issue except neither one of them can open chat or anvils without the switch also freezing. The game is nearly unplayable on the nintendo switch.