For me it seems that it's more that the few people at helm didn't really bother to learn any modern language or update themselves on theory so it feels like sli

For me it seems that it's more that the few people at helm didn't really bother to learn any modern language or update themselves on theory so it feels like slighty nicer 90's language, not something developed recently. And their weird entrenchment in "doing things the way plan9 did" Hell, how you design a statically typed language and go "nah, we don't need sum types! That's too complex!"...