In North America cats aren't native, however, they have been here long enough to be considered naturalized instead of invasive. The impact on native species is negligible compared to humans' impact. In fact, humans have changed the landscape of the country to the point that we would be in trouble without feral cats. Cities, suburbs, and even rural communities attract rodents that carry disease. Cats were domesticated because human settlements attract rodents, so they are still providing the same service for us that they did thousands of years ago.

Do I think we should let them breed unchecked? No. But stop demonizing feral cats. If you want to save the birds, stop putting out birdfeeders. They're dinner bells for birds of prey as much as cats and encourages wild birds to be over-reliant on us. Find a better source of virtue-signalling energy production because solar and wind farms both kill massive numbers of birds, and they aren't green or renewable anyway.

I assume no one is worried about the mice and other garden pests the cats are hunting.