There is not a lot of new money in crypto these days
So your whole question becomes kinda meaningless if this assumption is correct (which seems to be the case). But if you in fact wanted to ask why people got into crypto earlier (like a few years ago), then the answer should be straightforward and it was easy money. Those who invested in early 2015, had patience to keep their coins till the end of 2017 and prudence to quit when the time came, multiplied their investments. That was the primary driver if we cut the crap and noise