Programming languages are tools. I couldn't care less about learning a new tool just for the sake of learning. My interest in learning tools is exclusively practical - if they help me do my work better.

I find functional languages interesting, but that's because I find the underlying theory interesting and worth learning for its own sake, not because I actually care about the specific language it's written in. Even then these days I'd rather learn about woodworking (which is currently my main hobby) than a programming paradigm I'm probably never going to use.