I feel like you are super trapped in a very small way of thinking.

Say I run an IoT system across a variety of embedded systems. I could dynamically load small behaviors & scripts to all targets with this. User scripts could target all devices.

Your aim that native code can target everything seems to be pretty limited. A lot of languages can't or won't invest in wide micro-architectural & embedded support.

I feel lile you are confining yourself to a very very narrow position, & refusing to see possible middle grounds or uses. We needn't adopt such stark framing.