This is entirely anecdotal, but my experience has been that many people espouse the speed of Python development when in fact they put out sloppy, non-production ready code that needs a ton of extra review, effort, and sprints to get up to snuff. I often find myself producing higher quality, production ready Python code than those who cling to it like a safety blanket and complain non-stop about how "slow" languages like C#, Go, and TypeScript make them.

On top of that, I believe that I am able to produce production ready code in other languages even faster than Python! Particularly when it comes to doing refactors for exploratory architecture in early POC/MVP; love the tooling assists so I'm not drowning in "is not a functions" and other dumb stuff while I'm working on hammering out interfaces, abstractions, and other structure.

Granted, I have almost certainly not worked with the best Python programmers, or the best programmers that happen to only use Python to put it another way. But looking at Python itself, the languishing ecosystem and stdlib, and every large OSS Python project, what does that even look like?!

So, I would say that yes it has a lot to do with familiarity and comfort... I'm very suspicious of people who insist on using Python and have little familiarity with anything else.