> there's other pretty important stuff that can still bubble up, like the person reinventing the wheel where a well known library could have been used

I wouldn't call not using a well known library "reinventing the wheel". The wheel in that expression is a concept, not a implementation. A library is an implementation of a concept. Writing yourself code instead of using a library is a great way to learn about what that library does and the tradeoffs it makes.

When I think about "reinventing the wheel" as something negative, I think about something like "Medical researcher discovers integration, gets 75 citations": https://fliptomato.wordpress.com/2007/03/19/medical-research....