Warzone 2100 (you can download for free as it is an old PC game that went GPL)

gets more on the nose by the day

That is just the gateway drug to bootstrapping.

Check out https://github.com/fosslinux/live-bootstrap

if you want the real hard stuff.

They already did: https://www.commanderx16.com/

you just probably want something better.

and that is the problem building higher performance requires more advanced lithography and that is expensive and until recently was not even an option for a hobbyist (without taking a mortgage on their house).

Given current stagnation, you need only wait about 10 years for that viable option.

rxvt-unicode with tabbedex.

I refuse to use a terminal emulator that needs more than 100MB of RAM to display 80x24 green text on a black display

Efficient is sexy