"No. Python 3 arrived quickly after many warnings. Then tools, tutorials and a looooooooooooot of time have been provided. This is nowhere Python's fault. It's the best damn migration story I've ever witnessed in my life. My only grudge on Python 3 is that it didn't break ENOUGH. I wished for stuff to have changed more."

I think you wrote a good comment, thanks!, but regarding 2 to 3, I think you got this wrong. I think a more gradual transition would have helped - people ended up putting off the porting work, which was easy because Python 3 was installable in parallel, and nobody was really using it etc., and then it really went dead for some years, which I think was counter-productive for everyone.

I think in general it's better to keep some compatibility glue code around until most people have migrated instead of letting a let's-clean-this-shit-up! frenzy prevail.

(Now hindsight is everything, etc. etc.)