There's a bunch to unpack here, on both sides.
To start with, I'll say that I agree with the mainstream view that cryptocurrency isn't actually creating wealth, in the sense of non-financial real goods that improve people's lives. It's redistributing it. Everybody's crypto gain comes at the expense of somebody else's crypto loss.
I'll also throw in that folks who say "HFSP" are often the losers, because they're the ones who FOMO in because of greed and ego at the top of the cycle and then panic-sell at the bottom when they actually become poor. The folks who are making millions in crypto are the ones who buy at cyclical bottoms - 2012, and 2015, and 2019 - and hold on to sell at the tops, when everybody else is making fun of the folks sitting on the sidelines.
However, they're on to something. Imagine that you're inside a group with superior military technology - the Mongols in 1200, for example, or an American settler in 1840 - and you're looking at the people you are about to conquer. Or less bloodily, you're going into software in 2002, aware that a computer program will replace the jobs of whole industries, and trying to figure out which profession to go into. It's much better to be on the inside of change than on the outside.
They aren't necessarily wrong, either - they're correctly perceiving that the fiat currency system is unsustainable and is its own Ponzi scheme, and creating an alternative Ponzi scheme to recruit participants into. Game theoretically, if you have an inflationary currency and a deflationary currency, it makes sense for everybody to spend the inflationary currency and save the deflationary currency (Gresham's Law) which further drives up the relative price of the deflationary currency so long as there's an excess of savings available. If we enter a time of shortages (which we might), then the value of the deflationary currency will collapse (since everybody needs to spend money, and merchants are accustomed to taking the inflationary currency) - but if that happens, Bitcoin and its electricity & Internet demands are screwed anyway. In the meantime, as long as labor and savings both remain abundant, holders benefit at the expense of new adopters.
The actual claim isn't that crypto is going to make everybody's life better. The claim is that it's going to make the life of holders better, at the expense of late adopters. People can't come out and say that directly - "Hi, I'm going to fuck you over and take all your wealth". I'm sure that'd go over great with the general public. So they say it in coded egoisms like "have fun staying poor", where you can write it off as somebody blowing off steam.