> Believing that all systems must be maximally flexible is a scarcity mindset that felt more reasonable when families had to save to be able to afford a desktop computer that would be in use for several years.

This is a good insight and it's entirely possible that general purpose computing was a historical aberration.

You say you want to be able to choose between a real computer and a restricted appliance, but how long will the market allow you to make that choice?

Selling locked-down terminals with access to a pay-to-play "platform" is obviously very profitable. How much longer will MacOS and Windows allow you to install unverified software?