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.
What bugs me is that somehow society lionizes people in the money industries over those doing equivalent service jobs like gardening, lawyering, much less more important ones like garbage collection.
If gardeners were paid 500k/year, they would be exalted. It has nothing to do with the work or the value provided to society.
People just love money and praise those that have it.