That history of Perl part seems a bit off. Perl 5 was wildly popular, and most of the early web was a mix of Perl 4 and Perl 5. People left for various reasons, many of them stemming from Perl 6 always being delayed and lack of momentum in Perl 5, but definitely not because Perl 6 was here and people didn't want to switch.

That's not to defend Python versioning though, which as a sysadmin supporting devs is always a pain point.