A language, its stdlib, and its package ecosystem all relate, but are also distinct. It's not hard to do your own TLS/SLS wrapper with whatever defaults you like. When I run `nimble search ssl`, it seems at least 4 people have done such.
This is just to pick on your example. There is surely much other technical debt in the compiler itself. The solution to low manpower, if you otherwise like Nim (or D), is to try to help the open source effort at whatever level you can: do your own packages, tutorials/documentation, etc.
Nim has some serious technical debt, and it seems they don't have the manpower for it:
https://github.com/nim-lang/Nim/issues/14719