That's plus for individuals but minus for languages.
Personal anecdote: I was exactly there a decade ago when I was working on Chrono, now one of best-known date and time libraries in Rust. Since I was simply my own, my design was not as good as it could have been. Of course it is still much better to have a suboptimal Chrono, but I can't deny that it remains and probably will remain suboptimal due to my design a decade ago.
This usually ends up in a situation where most of the significant libraries for the language are abandoned GitHub repos with 13 stars and no documentation ("You just have to read the code!!1!").
Compare to other communities where you need to stand out from the noise.