I added information.
OK. I'll try them later.
iPadAir3rd iPadOS v15.3 and iPhone12 iOS v15.3.1
Same bug in ios
[iPhone12 / iOS15.1.1 / MinecraftBE v1.18]
I'm having the same problem.
Before 1.18, I played multiplayer games with about 20 people, but there was almost no lag.
After the 1.18 update, even about 10 people will have a terrible lag for all players.
The destruction and installation of blocks and the loading of terrain when teleporting are very delayed.
Chat is not delayed.
There are no errors in the content log, so I don't think it's a syntax error in the command or add-on.
Also, the auto save icon is displayed every few seconds.
Maximum size seems 30x30x30 in 1.19.20