[brundolf]

I've been using Rust for about five years, but I've never been paid for it and I'm not sure I ever will be. I just like it!

Personally I don't think it's worth trying to predict which technologies will be the most valuable and learning them based on that, unless you're struggling to make money right now. It sounds like Swift is working great as a money-maker for you right now, so I recommend just following your interests outside of that! Maybe they'll lead to another money-maker, maybe they won't and that's okay

I don't see Rust eating any domains outside of low-level systems development anytime soon, so I wouldn't worry that you're going to get left behind or something. It's not going to make Swift, or JavaScript, or Python, or Java, or Go, or many other things obsolete