The (a) scams and (b) insane volatility.
The folks you are alluding to who fall into this category are the least sophisticated and most desperate. This makes them easy marks. They shouldn't be buying into unregistered securities to resolve their banking problems. That's how we got the Great Depression and why we not have an SEC.
Further, these folks are disproportionately affected by the insane volatility and high fees of the crypto space.
These so-called financial products are just proxies for US dollar liquidity in the global financial system. If we had to write a prospectus I don't know anyone who isn't a money manager who could figure out how to actually deploy this sensibly. Let alone a homeless person without an address. How are they to 'do their own research'?
Something that makes the problem worse isn't a substitute for a proper solution.
In the US you generally need an account at an AML/KYC exchange to buy crypto for dollars and a bank account, so already we're off to a bad start. Or you can use a bitcoin ATM, which costs like 20%, dramatically worse than predatory lenders.