fully agreeing with what @mnxn said, I find OCaml appealing, because
- compact and comprehensible code as typical for functional languages,
- static linking possibility, create self-contained binaries that run with no dependencies and survive OS updates well,
- runtime performance so as you can target tiny machines like raspberry-pi zero,
- no GAFAM inside, i.e. not controlled by a monopolist but rooted in educational background.
The last point may be the weakest, because of the worrying github dependency (now the M of GAFAM) of the ecosystem.