What modern mainstream language is smaller than Python? Ruby? Javascript? Go is surely smaller but then your library surface area as well as code since increase correspondingly.
Python has a lot of things in the standard library, though I think the tendancy has been to stop adding things (case in point: I believe there is very little argument against putting requests into the standard library. I get why they don't but I disagree with the reasoning)
Yep you're right, there's even an official effort to clear some of these out: https://peps.python.org/pep-0594/
You didn't ask about relative usage. You asked for a mainstream languages smaller than Python. Lua almost certainly is.