I will stick up for this person. I agree with all of the points listed here. But especially: Python version management and installation sucks. A while ago I had a broken python ship with my Ubuntu desktop. Pip decided they were going to deprecate behaviour, and nobody updated or tested on Ubuntu. Also it is slow and ugly. Just write it in Golang or something.
Version management is pretty easy to solve: Just use virtualenv and you won't have a problem. If you start messing around with system level python package installs, you'll likely make a mess. As for ugly, I disagree and find Python some of the easiest code to read. "Slow" depends on the application. For 90% of the apps out there, you're waiting on something else (network IO, DB, etc.) and it's fine.
I like the library `invoke` for scripting A LOT, I just prefer to write my larger software in other languages.