Because of the Fed, which is an organization many people don't want manipulating (devaluing) their currency. Monetary freedom is a big draw for many in the crypto community.
Sure, but one could argue that our sanctioned manipulation of fiat currency is similarly based on delusions of simplicity and/or understanding. We still don't seem able to reliably avoid recessions, and no one is predicting the market with any reproducible accuracy.
Perhaps such complex, chaotic systems may be better off sans regulation. Especially something like cryptocurrency, which does not have the same properties as paper fiat, although it is being treated as such.
I personally have less faith in institutions run by humans and bogged down by dated regulations than I do in an instantaneously fluctuating near free market. If you can't trust people to invest in currency because of complexity, what makes you think you can trust them to regulate your money, and make decisions that affect the value of your assets for you?