You're obviously entitled to your own opinion, and certainly IPOs carry much risk. That "insiders" get made liquid is not, IMO, one of them. Somebody who invested in GOOG on day one would've made over 10x on their money today. Somebody who did the same in ZNGA would not. It's obviously very risky, with potential for commensurate reward.
I'm not sure why you think the markets have "failed to deliver the economic growth" over the last 15 years, or that it's somehow their job to "deliver" economic growth. I think us "little guys" who have invested in the market in that time have done very well on balance.
I'm not one for long back and forths, so feel free to have the last word if you'd like it. I replied initially because I'm very much turned-off by the save-people-from-themselves philosophy.
You quoted Buffet, I'll quote Jesse Livermore: "t was never my thinking that made the big money for me, it always was sitting."
If you think the "little guy" is screwed over by the "big guy", become a buy-and-hold investor. There's little way to be screwed there. Spread your bets out--diversify--and buy and hold. When it comes to trying to time the market or play ER or day trade, you're right, it's hard for a retail investor to make a buck. So buy and hold and let the stock market help you accumulate wealth the way it's done reliably for over a hundred years.
To me an IPO is very much a conflict of interest situation with asymmetry of information. There are laws to govern this but there is a huge gray area.
Once a company is public it's a little different...
In my opinion capital markets have been getting more broken in many ways and have been favoring the big guys over the little guys in many ways. I say that as someone who invests in the markets, have benefited from stock options and pretty much seen things from many different angles. In the last 15 years capital markets have failed to deliver the economic growth and the gap between the rich and the poor has widened.