@bigfoot

90 % of this can be solved by treating/thinking of AOS/MOS more as an "environment", than an operating system.

All you have to do is run multiple (maybe hundreds) AOS/MOS environments (which is extremely lightweight anyway) side by side at the same time under some real modern memory protected SMP OS like Linux or if you want even your own NonBackwardsCompatibleModernMorphosSMPOS.

In similiar way to how AROS hosted runs under Linux (or under other OSes).

So for every (or at least every "big") app you "boot" a full new AOS/MOS style environment process (depending on what AOS components the APP uses, you may also have different sized AOS/MOS environments to reduce host resource usage).

The apps end up in different host (Linux) process so are 100 % memory protected against each other.

You can mix 32 bit apps (booted from 32 bit environment) and 64 bit apps (booted from 64 bit environment) at the same time.

You get resource tracking for free (host process exits -> all resources freed).

Multi core: app #1 may run on core 1, app #2 on core 2. Not quite SMP, but still ...

A single 32 bit app may be limited to 2GByte of RAM, but all the apps together may use much more than 2 GByte.

Btw, isn't that Linux "Docker" stuff somewhat similiar in concept?