Has a potential connection and dependence with https://report.bugs.mojang.com/servicedesk/customer/portal/6/MCPE-224958
A game with large Addons (for example, RealismCraft) also causes lags on iOS. Any conditions for the world to be voluminous and large lead to this bug.
I can confirm the existence of a bug.
Affects 1.21.100, 1.21.101, 1.21.110 Previews.
This bug occurs on all iOS devices. And I'm not the only one facing this bug. This is an internal error of code optimisation of the Bedrock edition for iOS.
Also affects iOS 18.6
Affects 1.21.90 - 1.21.100.