I think you're missing the point why younger people do that. Real wages have been deteriorating over the years. It's much more difficult to afford a house today than it was 50 years ago. People are perfectly aware that investing into index funds is the "correct" approach, however it does not solve anything for them. They're desperate and for them _to gamble_ seems like the only way to become decently rich allowing to escape the rats race, otherwise there is not much to live for, just slaving their days away. That's exactly what led to the recent situation of en masse margin calls in Korea.
Here in Europe I too have been working for years and I just don't feel like I'm earning actual money. Most of my income is eaten away by taxes and very basic living expenses. ETFs won't compound for me much if there is not a lot invested into them in the first place. This is exactly what led me to despite high electricity costs to buy 2x open source bitcoin lottery miners (NerdQaxe++) and just hope for the best.