The language you're writing in has next to no meaningful impact on long term maintenance. When you're trying to do software archeology on why a function even exists the types it has will not help you figure out it's there because between 1996 and 2002 there was a tax rebate on capex for rocket development.
You need human understandable documentation, not fancy language features. This is no where near as sexy so no one does documentation and we're in the middle of a digital dark age.