Hi. As Xperia 10 II has aarch64 CPU (aka ARMv8), it is basically possible to run 32 bit arm applications (ARMv7). It is even enabled in kernel used on 10.II. I tried it with statically compiled Busybox:
[defaultuser@Xperia10II-DualSIM ~]$ file /tmp/busybox
/tmp/busybox: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), statically linked, BuildID[sha1]=547c84601e0a4b885689ceedf55256f451ad401a, stripped
[defaultuser@Xperia10II-DualSIM ~]$ /tmp/busybox ash --help
BusyBox v1.31.1 () multi-call binary.
Usage: ash [-/+OPTIONS] [-/+o OPT]... [-c 'SCRIPT' [ARG0 [ARGS]] / FILE [ARGS] / -s [ARGS]]
But to support even graphical 32. bit applications, Jolla would need to build and pack almost all libraries twice. It would increase image size significantly and maintenance would be hell (even bigger than it is now).
Moreover, running armv7 binaries on aarch64 kernel is not without problems. Armv7 kernel allows unaligned memory access in user-space applications (cpu exception is handled by kernel - slow, but works). But aarch64 kernel emits SIGBUS in such case. So, some applications that works fine on armv7 hardware may have problems…
I fully understand the decision to do not include armv7 userspace to aarch64 Sailfish.
I’m missing many native apps since there’s not a 64-bit version of them.
Please name these applications. Sources are available for most of SFOS apps. Try to contact maintainers on Github or OpenRepos. Re-compile popular applications is simpler than add full armv7 support.