I guess it has poor (or nonexistent) unicode support in 48kb. My only gripe with NetBSD was its lacking UTF-8 support for many core tools (eg. wscons, vi) when I used it as daily driver beck in the days (NetBSD 5 RC2 times :P)

Nope! It has fully working UTF-8 support.

Wow! Nice!

… and multi-byte character set support was added for nvi2 about a decade and a half ago.

* https://jdebp.uk/FGA/vi-family.html

but according to the docs not to the nvi version in the base system.