I think it strongly depends where you live. For most people living in urban areas and such, inside is the best place for them. But I myself live in a rual area with lots of open room and almost no traffic, so I've always had my cats outdoors and they seem to be very happy. I think it's good that they can still have the human contact and love, but at the same time can use their natural insticts to explore.

have five indoor cats, while my oldest male cat is goes in and out; the dogs also have access to the inside of the house; the fish live in the kitchen to entertain me as I cook dinner

Yes!
The outdoor cats life-span is 3-5 years riddled with diseases and injuries whereas the indoor cats life-span is 15-22 years. If you are responsible and love your cat you play with them daily and provide plenty of exircise and stimulation, nutritious well-balanced food-wet and dry and if you don't have the luxury of a catio you can walk your cat on a leash. Mine love it. So they don't miss out on anything but the bad stuff!!

Yes, for their own safety.

mine don't go outside.

Cats should be out some of the time but because I am a bird lover I feel there should always be someone with them.

Most of the time. They can be taught to walk on a leash, the same as dogs.

absolutely

Indoor and out doors.But then again., it depends where u live

Most of the time.