Ultimately, most good ideas were first implemented by Fabrice Bellard.

I am happy to see him working on QuickJS in the last month or so. It could really use some ES2023 love!

Copy and patch goes all the way back to Grace Hopper's original compiler implementation

They were called "template-based" JIT and copy-and-patch approach is not new in this regard. The novel idea of copy-and-patch JIT was an automatic code generation via relocatable objects. (By the way, QEMU is indeed cited as an inspiration for copy-and-patch JIT.)

Heard of him; he's done a lot of stuff. So is he the Bourbaki of software?

https://en.m.wikipedia.org/wiki/Nicolas_Bourbaki

While I'm sure some people theorize that Fabrice Bellard is actually a pseudonym of a collective of 10x programmers, he is as far as I know just one person.

He he, I forgot to add a wink at the end of my question above.

Which itself is how I understand the compilation step of quaject code in the synthesis kernel to have worked. Ie. do constant propagation and dead code elimination on the input format, and use a simple template driven backend to dump out native machine code.

In fact I wouldn't be surprised if the earliest compilers were template based, as that's about the only implementation that would fit in a RAM as a compiler pass.