I think people do this for every language. It becomes a part of their identity, and then they have to defend it. I used to do that too, long ago, but I don't have the time or energy for it for the most part, and find it boring, so that $LANG-user-as-identity bit of my has fallen by the wayside.

I don't think it's about adoption levels; sure Go and Rust are tiny compared to JS/python/etc. It's emotional, not about who has the most users or who can even plausibly get there.