Arno van den Brink

I experience the same on my iPad Pro (A1670) . This is the crash report Codex made after analysing the IPS file and game logs

Minecraft startup crash — diagnostic extract
Device model identifier: iPad7,1
OS: iPadOS 17.7.11 (21H461)
Minecraft: 1.26.50 (1.26.50.04)
Device, OS and version from the previously supplied Apple .ips report.

Exact lines from minecraft-live.log:
Line 28444: Sep 15 21:45:35.808386 minecraftpe(Metal)[446] <Error>: MTLValidateFeatureSupport, line 6575: error '<private>'
Line 30392: Sep 15 21:45:36.319777 ReportCrash[124] <Notice>: ASI found [libsystem_c.dylib] (sensitive) 'MTLValidateFeatureSupport:6575: failed assertion `Texture Cube Array is only supported on MTLGPUFamilyApple4 and later.'

Matching stack in the earlier .ips report:
Rendering Pool(0): Minecraft -> AGXTexture initWithDevice:desc:isSuballocDisabled: -> MTLTextureDescriptorInternal validateWithDevice: -> MTLValidateFeatureSupport -> MTLReportFailure -> __assert_rtn -> abort (SIGABRT).

Conclusion: texture cube array creation fails the GPU feature support check. The exact Minecraft feature requesting it is not yet identified.