I used to work with an organization that did this but they ran out of money and closed.
You're doing just fine on your soapbox. (Though that it no way means I agree with all you're saying! )
I personally know or have known a few people who on their own trap feral cats, have them desexed and ear-clipped, and release them back to their colonies. Mind you, these are just random people I know. I didn't meet them through any kind of animal-related contact. I think it would be pretty easy to get that going in various neighborhoods if vets and shelters would agree to free/very low-cost neuters. We also have a local BBQ place that hosts a feral colony, but I don't think that's intentional.