Those are considered niche compared to Rust or C++. Rust has a large ecosystem around it and at least one large sponsor (Mozilla) and used in production by others like Cloudflare, Yelp, and npm.

I think Nim and Zig are both quite interesting and potentially very productive, but they have a long way to catch up to Rust in terms of community support.

Not being corporate-driven is a feature, not a bug.

Corporate sponsorship is just an example of the level of support that exists for Rust. And it's Mozilla I'm talking about here, not your typical corporation.

Certainly other languages were able to become widespread with large communities and library ecosystems without being directly sponsored by a corporation, such as Python or Ruby. I tend to think of those as associated with an individual, Guido or Yukihiro, though I know in Guido van Rossum's case he's worked for Google and Dropbox, though that was after Python was in wide use at those companies.

Whereas with Rust I think "Mozilla" not "Steve Klabnik", because it was corporate-sponsored from the beginning and worked on by a team.

And if you want your favorite language to grow into its potential, you need funding, and corporations have a lot of funding to put into things like potentially productive new languages.