One day cryptos might boom in such a way that basically everyone who didn't invest in them will become poor
Lol! I think this line is an exaggeration

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What if they have not invested simply because they have investments other than bitcoin and they just decided not to be involved in cryptocurrency? Though your speculation can also be true but I dont think everyone who did not invest will become poor and what if everyone did, will there be enough to make everyone millionaire or billionaire in the whole world?