Sure, I've found some gems on CPAN, but, having worked on both Perl, Python, and Java at reasonable scale for awhile, I cannot understand all the praise CPAN gets. It's the worst-quality scripting language package ecosystem out there. Even NPM does a better job, and some things about NPM are awful. CPAN might have been the first/only/best package manager for a get-shit-done scripting language at some point, but not any more.
Separately, I agree about modules which extend language functionality (e.g. class systems, async programming, runtime typing) specifically. Perl does pretty well in that area. While many of those language-extension modules really don't play well with any other metaprogramming tools being installed in the project, I don't imagine that any alternatives in other languages do, either. My main beef above is with "simple" (read: not pervasive semantics changes) modules like IPC utilities, HTTP clients, or loggers that don't know how to stay in their lanes.