Perl's decline was cultural

Should the Rust community take a lesson here, and maybe the Zig community to an extent?

To me it seems that some in the Rust community in particular, perhaps because they're just the most vocal, are tightly coupled to progressive, social activism.

I guess in general I just find myself wishing that political and social issues could be entirely left out of technical communities.

Agreed. The Rust community is an incredibly toxic place because they are so determined to involve politics in tech. I love the language, but I stay as far away from the community as I possibly can.