I've tried Elm and I think it's really great. I've watched a handful of Evan's conference talks and I respect him a lot.

However, when I choose what tech to go deep in with my limited free time, I want to see more than zero mentions of it in the "who is hiring" threads. I don't feel like Elm's traction has gained any in the two years since I first dabbled in it. If I was in a position to pick the tech stack for my work, I'd give Elm serious consideration though.