It's insane to me how making the technically worse choice is okay to you because some company out there is "making it work"

Also what could you do in 3 mere days that would pay off more than having the code in a language that the team is much more efficient with, one which doesn't need hacks to "make it work"?

It would save you several days on features forever, compared to doing one thing for just 3 days.

Basically, you have said it: It is about what the team is knowledgeable about.

In my book Nodejs doesn't belong on the server, but that's the choice they made. Python at least is thought out as a backend language, but can also be criticized for many aspects. If a team is more knowledgeable about modern languages, of course there are many technically probably better choices than both Nodejs or Python.