I read your post carefully, and I even agree with parts of it. There are major modules/module families that don't work together.
However, that's light-years from the claim that I quoted.
There are a lot of different ways of doing the same things in Perl the language and in the CPAN ecosystem. That's a strength and weakness. But in my experience, the authors of most of the modules care very deeply about doing things in a sustainable way.
I agree there is a lot of dross on CPAN. I've also lived the frustration of seeing two kinds of exception handler TryCatch vs Try::Tiny in the same subdir of a codebase. The issue is really that a lot of basic modern functionality requires CPAN, and the core of Perl 5 is small and mostly not super helpful. Something akin to Moose in core as the new standard way to do OO would have been a good plan 10 years ago.