Oh wow I can't imagine keeping them inside! We have cats and dogs fed on raw food and omg, that would be a nightmare. My dog already got one of my chickens once when she was chilling in the backyard when they ran out. Lucky bird is still alive tho! Thank you blukote!
We are pretty rural so a lot of people here keep tough farm animals and would probably skip a lot of the steps we do. We try to walk a line of having rugged birds with modernized, hyper ethical treatment and while I'm sure inside chickens are totally more common than they used to be, as far as I know it's still pretty much the norm to keep them outside once they're out of the incubation stage. We also try to avoid over imprinting on the birds too, and setting them right outside helps both of us. While it's sweet when one of the chickens wants us all the time, it affects their place in the flock and we have seen it cause stress.
Every flock is different though! You do you! As long as people care for them properly I think lots of methods are awesome and necessary