[mrisoli]

Because it's easy money(and as others said, to stay employable).

If someone created a framework yesterday there are few experts, and they won't judge experts by years of experience, if you're a relatively new FE in the job market would you go compete with people with 15+ years of jQuery and 8+ years of React or just take on the next new thing?

If you pickup the latest tooling today by the time it's widespread(like React is now) you're way ahead of the crop and it's quite easy to get some nice pay out of that.