> that is probably 10% of a PL if you want it to do something people will actually use

I think this is really understating the challenge of generating machine code that is competitive in terms of size, performance, etc. with state-of-the-art compilers. I'll be the first to agree that it's far from the only (or even the biggest) difficulty in PL, but it remains a huge chunk of engineering work. The interesting part of this experiment is how much of that work, as a percentage of the work of building a programming language, is now given to you for free, for a language that is indeed mostly ‘just a syntax wrapper over C-like functionality’.

(Of course, a big part of ‘people will actually use’ is nothing to do with the language at all, but the next twenty years of building an ecosystem and community buy-in.)