I've found the idea that modern VR is a "fad" comes from people with limited VR experience. It's not their fault, since cheap consumer VR like the standalone quest headsets is mostly limited to what amounts to the equivalent of mobile games -- they're toys.

I own a relatively expensive setup and have experienced the top tier of what consumer VR has to offer: it's incredibly impressive. But that also highlights the issues. Quality consumer VR is expensive, fiddly, and currently has an extremely limited/niche number of worthwhile games and experiences.

The reality is the current tech is really the first generation of practical consumer VR with capabilities beyond "headache inducing novelty". It'll never replace "2D", it still needs to come down in price, but it's hardly a "fad".