Craze - Yes, reason can be as simple as PM roles give more opportunities (career/monetary). Many non-tech folks are able to join mainstream tech through the PM gateway only. Remember, anyone can do tech, it’s just some tech bros who want to build high walls with their egos.
Worth the hype - It all depends on individuals situation. If you’re making good money and have skills in other areas, why you wanna leave that? PMing is good and worth if you can deal with ambiguity & communicate effectively.
Supply & Compensation - These supply, demand issues are not the same if you see at various levels of the pyramid. Ask any PM leader, how easy/difficult it is to hire in this market.