Learn just enough about the fads so you can hold a conversation about them, but don't invest heavily in every one of them. You don't need to tech hop every year - give things at least a couple years to shake out. This will let you skip a lot of the time wasting BS that comes with fad driven development.

This is great advice. The other thing about learning a little bit about all the new fads is that you can fairly quickly figure out bits where going a bit more deeply will help you out in general. For example, I would not recommend using React for every front end project (or even most ;-) ), but playing with React and understanding what it was trying to accomplish legitimately made me a better programmer.

This. This is how I treat customer fads as a consultant, so far to good effect. Consulting isn’t too different than interviewing for jobs, especially the part where you have to convince new customers that you know what you’re doing and are worth your rate.