I think it's true, but also a red herring.

A lot of corporate dev environments operate on a policy where you're basically allowed to fix things that sales and customer support explicitly ask to fix, but nothing else. Which in turn means an environment where doing maintenance work that indirectly sustains the software is off-limits. Which in turn means they never ever upgrade the underlying platform (that's off-limits maintenance work), and so they end up on an EOL'd platform. At which point they blame the platform, and announce they're going to switch to something better that doesn't impose this problem on them.

Those types of places were never going to upgrade to Python 3 under any circumstances. They probably would not have even upgraded to a completely-backwards-compatible Python 2.8, if that had been released. So blaming Python 3 is a red herring here.

Google replacing python with Go?

This also isn't really true. Google is certainly replacing certain things with Go. But its not replacing python with go.

I understand that had more to do with their "Unladen Swallow"[0] work being rejected than anything related to the transition to Python3.

Since Google couldn't convince folks to let them make Python faster, they created a NEW language instead.

[0] https://www.python.org/dev/peps/pep-3146/

That has little to do with Python 3 and a lot to do with the scale of Google's services where high performance is really important and where refactoring in static languages is easier.