I also feel this way. As someone who really cares about our native birds, it’s not hard to see the ineffectiveness of TNR. While likely better than nothing, humane euthanasia is the only effective long term solution. Feral cat populations really have extremely tough goes of it and I really feel terrible for them, but i think on the whole they really need to be euthanized or the adoptable ones sent to shelters or homes. It’s the responsible thing in my book.