I believe to boils down to the one major hurdle to cryptocurrency adoption: for big, serious (read: institutional) money to get involved, it needs to bridge the gap between the unregulated, freewheelin' world of crypto and heavily regulated world of traditional financial institutions. That manifests in two distinct problems: how to get your fiat money into crypto, and how to enable financial instruments to operate in crypto space without the risk of being shut down by the government.

The answer to first problem are supposed to be 'stablecoins' which get you one coin for one fiat unit, and keep that peg (1$ = 1 Tether, for example). You exchange your dollars/euros/pounds for stablecoins and then trade with them for other cryptos, with your investment always having a way back into fiat money. So far, none of the stablecoins have managed to fulfill that promise.

The solution to the other problems (how can Goldman Sachs work in crypto space) are supposed to be security tokens, which would be blessed by regulators. But, none have been approved yet.

Consequently, crypto space remains a sort of financial Wild West where there is a lot of promise, but so far most of the attempts to do something actually useful turn out to be cautionary tales and illustrations for why we have heavily regulated financial system in the first place.