I live in north Texas. Every feral cat out there is one less house pet the owles and coyotes eat.
Can’t see them ever becoming a problem here. They are not that high on the food chain.
I lived in Western Kansas for 5 years. I spent a lot of time outdoors but don’t recall ever seeing a cat of any kind. I guess the prairies are just not cat territory.
Here in the NW Florida woods, the cats do pretty much what they want. We have coyotes but I don’t think the cats have much to fear from them, at least if there is a tree nearby.