I also have this issue on an IPad 7th gen running IPad OS 18.7.7, restarting the iPad did not fix it, neither did reinstalling Minecraft. I believe the cause was something in either version 26.50 or 26.51 Since it broke after installing those updates. For me when I open the app it shows the Mojang studios screen before switching to a white screen there it either crashes or freezes (not the entire system but nothing happens). It produces no logs.
Also Happens to me on my iPad 7th gen running iPadOS 18.7.10 as well as
when I was on iPadOS 18.7.7. Here are my crash logs, at first it didn’t make any logs but now it does