Pe is good when it is taking big risks on something new. That is hard so that is not what most pe does. Most pe is just figuring out ways to insert artificial inefficiencies into the system to syphon money off. Ie tax arbitrage, patent/copyright abuse, geographic or other market power abuse, etc. Basically find a way to move money around the system with no net benefit to society while having a bunch of it fall in your pocket is 90% of what pe does and its poison. The other 10% is vitally important to continued growth and prosperity and its often hard to tell which is happening until its over.