As a small animal doc for 20+ years and an amateur wildlife biologist, my experience and research says you're spot on, Leo. At work, I never saw an indoor only cat suffer from- being hit by car, dog attacks (well very infrequently), felv, fiv or rabies, starvation due to being locked in the neighbor's garage for 3 weeks during the summer vacation months, losing a leg to spring or snare traps, being shot, rodenticide poisoning, hookworms, giardia, roundworms, lung worms, liver flukes, ticks, infectious anemia, etc., etc.. Also, more then a few endangered species of frog are being decimated by both feral and kept domesticated cats along the coast of GA and probably elsewhere... I saw a "go-pro on a cat" video during a lecture about this issue at a professional conference, and during the video, the cat, fed twice daily at home, still went out one night and ate 26 frogs!
https://www.researchgate.net/figure...-Georgia-USA-2014-and-Kittycam_fig1_326553030,
https://wildlifemanagement.institut...ts-outdoor-cats-kill-more-wildlife-previously. I understand that cats have historically served as mousers/vermin killers, but most people keep them as pets these days and they definitely don't belong outside if that's the case. I hate scooping litter pans... but I'm very good at it.