There seems to be a big difference between Britain and the USA as regards letting cats roam. In Britain it's absolutely normal, and every pet shop sells cat flaps to fit in a door to let your cat have free access in and out. Very few people rig their gardens to keep their cat in. (Some rig their gardens to keep cats out - the same company exhibits at cat shows and garden shows, with the same product, promoted for diametrically opposite purposes!)
We accept that there are dangers, but unless there is a very busy road or the area is very urban, these dangers are not considered sufficient to justify keeping cats in. Of course, we don't have coyotes and so on.
I've heard Dogdoctor on this forum on an absolute rant against people who let their cats out, considering it to the the height of irresponsibility and selfishness, indeed cruelty. It's quite a common view in the USA, that cats should always be confined. So really, wherever you are, someone else's mileage is going to vary.
Rolfe.