The two main issues I have with them are that firms tend to give them to just about everybody (instead of just to folks working very directly with real IP), and they only pay base salary, not something closer to actual total compensation (often multiples of the base pay).
Having said that, the quant firm is relatively unimportant and not a good reason to prevent a total noncompete law. It's probably better to just ban them then try and make allowances that aren't full of loopholes.
I know this will not resonate with some, but on some level I do not really subscribe to the idea of intellectual property. My personal belief is that the brain is more like a radio receiver. The ideas are floating out there for anyone to pull down. The more sensitive among us are able better able to hear what is there and report it back to the rest of us. To claim ownership of an idea is to me like claiming ownership of the note A or the pythagorean theorem. Of course there should be some rewards for introducing novel ideas to the world but to me the real reward is the creative experience of bringing something into the world that was previously unknown.
In an ideal world, I do not think that hedge funds (or most fintech) would even exist. It sort of offends me that we would waste our civic resources legally enforcing ip rights. But I also understand that my position is far from universal.