your bias is showing.
I'm not sure what you consider hot tech but I can assure you whatever it is it is based on tech that has been around for ages and has just been rebranded. I find that people that hop from "hot tech" to "hot tech" don't ever build up a depth of knowledge and understanding to tackle hard problems in an elegant way. It is essentially a major contributor to the 1 year of experience repeated 10 times phenomena.
You immediately assumed that the folks I found are just jumping from tech to tech without building anything substantial. Which is probably also bias, just an opposite of mine. You also assumed that I didn't vet them or test them on "elegant solutions". Maybe your heuristic worked for you. But this heuristic, in my current situation is thus far working for me.
Maybe that's why many of the major changes you see in tech, like Linux, Git, Vim or Redis started as a single person's work rather than a clever corporate product.