Python lost a lot more due to the constant flamewars about the transition, how many people wanted to just not care about py3 for many long years, etc.
languages that are actually growing in userbase/popularity are not static. this is hard to accept for many users of popular languages.
I fail to see how that is true. Python was already catching on in a big way back during python 2.7 and I'd guess it probably lost at least 18 month worth of momentum building with python 2->3.
I'd say Pythons popularity today is at best unrelated to python 3.