I've had similar suspicions. The golden rule that once something becomes popular, it turns to shit. For the prior generations it was exhausting social systems. For the current generations it's stock market based funds.

I'm thinking probably if you weren't heavily invested into this before about 2015-2020 era, then you're probably going to be late to benefit from it before whatever disasters await. More definitely the whole memestock era was a high water mark.

Also as the first reply said, it's not rigidly defined generations. Gen-X is a relatively small generation. The first half of millennials are probably just as big if not more invested into stocks. Public discourse has pinned millennials as close to gen-z and memory holed that the bulk of millennials are 40 give or take a few years. The difference between the two halves is by a wide margin.

Gen-X is only a few years away from drawing from their investments and becoming net spenders. Many of them would already be doing so. The ones who retired early.