Anyone could speculate and day trade before just as long as there was enough information available for retail investors to do so safely. That is, on the public markets.

Private markets introduce much higher degrees of information asymmetry. Maybe you'll get rich, but your odds of losing your money are also much higher. The basic theory of accredited investors is, "Unsophisticated players aren't allowed to gamble unless they can afford to lose."

I'm fine with that. I don't want to pay for the retirement of somebody who got talked into sinking their retirement funds into something that was fucked from the start. If we want to give people a cut of the proceeds of innovation, let them put their money in funds that in turn invest a reasonable proportion of the money in high-risk areas like VC. There the asymmetries are drastically reduced.