OK - apparently iOS 14.2 does allow JIT for side-loaded apps (not App Store) via the CS_EXECSEG_ALLOW_UNSIGNED flag. Maybe this will be allowed for store apps in some future version. Fingers crossed!

All previous versions of iOS do not permit execution from writable memory.

Via https://9to5mac.com/2020/11/06/ios-14-2-brings-jit-compilati...