There's something to be said for having a deep familiarity with a language. In terms of just churning out basic tasks like churning out CRUD endpoints it maybe doesn't matter so much, but it's both a force multiplier for productivity and an enabler of building something altogether less trivial.

Arguably a lot of the ways modern software sucks is a direct consequence of developers not understanding the tools and languages they're using. It's a bakery that bakes bread by scraping the toppings off frozen pizza.