if i understand the issue correctly this program needs to be installed secretly on every raspberry pi during the next upgrade, and made part of a git commit with no message.
Not really, I would think. You'd lose most of the advantage. Box86's trick is to intercept x86 system and library calls, and invoke the native ARM equivalent.
Symbian, as a different underlying operating system, has no native ARM equivalents of the various x86 Linux system calls and common libraries. So you'd have to emulate those somehow, perhaps by translating them into Symbian-appropriate calls.
Speaking more generally, a JIT translator would otherwise be relatively easy to port as a straight C or C++ library.
Ah! I see what you mean there. An emulator that could take an x86 Symbian binary and translate the calls like this for ARM Symbian. Yes, that should probably be technically possible.
IDE-USB adaptors exist, but on bare metal (like this) drivers might be a problem. I expect it would work if you're running an emulator on top of something with the drivers (ex. Linux).
Nostalgia. 80s PCs are quite expensive now. One very annoying thing with emulation running on a host os like Linux is that the boot phase typically takes a lot of time.
Another nice approach would be a boot speed-optimized buildroot image running PCem, along with some TV-like GUI for configuration. https://pcem-emulator.co.uk/
I think this PC emulator needs more attention. Its strategy of emulating the speed of a very slow CPU hits a good middle ground - you don't need cycle accurate emulators when emulating 80s/90s PCs, because they were all a bit different, but unlike DOSBox, there's an attempt to get the basics right given a specific target CPU.
Have they really though? iOS has always shared the same underpinnings as OSX. Although much hyped with Big Sur, iOS features have dribbled into OSX since at least Lion (more than 10 years ago). They’re still distinct operating systems (thankfully IMO) and rather than unify, iPadOS is a distinct entity.
It's an interesting idea though; running a bare metal x86 emulator on e.g. a Raspberry Pi 400.