It seems like Python 2 is still pretty prevalent, with over 40% of new downloads taking place as of last year. And people forget Python 3 was originally introduced in 2008. So the transition is taking decades, not years.

The last place I worked was still using Python 2 as of last year, and they were a startup without all the bureaucracy of a big company. They also had plenty of money and engineers. Python 2 is still the default for everybody I know.