My answer to this point is that it's no more good or bad than a basic phenomenon like fire. Fire will burn you out of house and home, but we've also harnessed it to forge steel and develop the internal combustion engine. So, is it good or bad? I think it merely "is".
We can't wish greed out of existence any more than we can deny the existence of fire. Socialists and utopians tried that and it doesn't work. The best we can do is harness it to do some useful work and try to mitigate its downsides. That, in a nutshell, is capitalism.
The problem is that most people don't understand that fundamental concept. Ask a person on the street what's the point of capitalism and they'll tell you it's to make money. If you don't have guardrails, you don't have capitalism - all you have is a feeding frenzy. You get the worst effects of greed, without the benefits.
The typical reaction is to decry capitalism as a failure, but it's not even capitalism at that point - just anarchy. The failure was allowing the machinery of capitalism to be deconstructed, like if you started ripping parts off an engine. Some of those parts might be holding back the engine from its peak performance, but they all have a purpose in keeping the engine running smoothly, efficiently, and for a long time.