I think you have a fundamental misunderstanding of a difference between " a blockchain " (the technology) and "Let people who see others making money hands over fist on a blockchain participate. I have this thing" (the fraud).
Blockchain the currency and blockchain the equity/bond/token were inevitable. The crypto world isn't concerned with traditional finance and their legacy rules. The future is decentralized companies financed with decentralized currency. It seems the people most offended by this realization are those with authoritarian complexes with a desire to control the voluntary spending habits of their peers. Which is exactly why there's demand for this new freedom money. Stop telling me how to spend and how to invest. I'm not your child and this isn't your money.
Even Bitcon has become surprisingly centralized due to ASIC miners. The simple truth is coins are 100% zero sum, so without utility they are limited to pyramid schemes.
So, yes in theory you could make a useful currency. But, nobody seems to be focused on low cost, ultra high transaction rates, anonymous transactions, etc. It's all pump and dump.
