I've been on a quest to eliminate build steps from web projects wherever possible. The side effect of that is that I've been using vanilla JS a lot more, and in turn have been learning a lot.
I used to *only* work with vanilla JS, and I was actually intimidated by jQuery at first when I started seeing it everywhere.
Learning a framework is always a little risky because you don't know how long it will be relevant. But learning vanilla JS always seems like a good investment for a web dev.