I have indoor cats who have outdoor privileges! They only go out for short periods of time with me to garden or get the mail and usually come right back in with me. I monitor them the whole time & they follow me around like dogs. I don't let them stay out at night because of possible predators, but their favorite thing is to go watch the deer eat in my yard @ dusk & then come running inside to get their own food. They are so infatuated with the deer!
I acquired three of my girls as outdoor strays & even though I tried to keep them inside, they were destroying my rental house in frustration, trying to bust out. I tried to compromise by buying an animal stroller & taking them on walks. Eventually, I let one come into the garden with me & she just followed me around, ate some bugs & followed me back inside! I couldn't believe it when the others did the same! They just hang out in my or my neighbor's yard. I think having lived outside & finding my house because of the bird feeders, they knew where they were & were content to stay, (maybe for the good eats I provide?). They're also extremely bonded to me & follow me everywhere like little ducklings!
Now that I live in my own house with lots of land in a very low traffic area, I decided to let the 2 previously indoor only cats see if they wanted to go out. I went through this long, slow intro to the outdoors thing, so they wouldn't be scared or get lost. Turns out there was no problem. They go outside the door, lay down & roll around and sleep in the sun. They're so cocky when they come in, it's really boosted their self confidence! But they still spend most of their time indoors.
When I grew up, our cats went outside, too, but eventually we kept all our cats indoors. I prefer that just from a welfare standpoint. However, I understand that there are some cats & some circumstances that are different & try not to judge others or myself for letting cats enjoy nature. If I could afford it, I'd have my entire backyard fenced in with special cat proof fencing.