It's not exactly proven and would be very hard to prove. That said, nearly everyone thinks electronic markets are better than the alternative. Any electronic market will open itself to algorithmic trading, so what most people are actually worried about are unintended consequences of changes to the current system.

That and for most people who actually understand the mechanics what is going on, the current system seems way better for the vast majority of people than the one it replaced, so we have little reason to change.