Newsflash, Go is fast. I'm sure those numbers will be worse in Py2 than Py3 as well, but aside from that what's your point? Python is slow so... don't switch to Python 3?
> Python 3 is adding features that other languages do better. Python smashes other languages in numerics, and approachability. Nobody needs 3 for numerics, and 3 goes backwards in approachability. If you're using 3 for its back-end tools, you're using the wrong tool.
Sure, people using it for numerical stuff might like Py2, but is that the only use case of Python? Should I not switch because you do numerical stuff? Django is great for backend stuff, as is the whole ecosystem (twisted, flask, DRF, asyncio).
Python 3 is also far more approachable than Python 2. Try explaining to someone why their program exploded after typing an umlaut into it, the magical "from __future__ import division" incantation or even the silly super() syntax.