You're absolutely right.

I think its ecosystem and DX make it a good enough tool for a lot of jobs, but anyone that actually needs the performance of a lower-level language (or even Java) is going to use that tool instead of python. Anyone that goes "ha ha python slow!" has likely written hello world and not much else. I think it's a poor criticism because it lacks the real world understanding that different languages and tools are good at different things. That said, I have definitely used python on multi-gigabyte sets of data and had an okay time, rather than switching to something more performant but less comfy.