It appears you don’t think cats should be allowed out, that indoor activities satisfy their curiosity, and they are fine with staring out windows , unable to discover. Now , if one lives on a busy street, I can see the concern . I have owned many cats ( my daughter has 4 , had others previous) , if cats want to go out, they should be granted that wish. Some are fine indoors with no desire to venture . I have one like that and I’m ok with it. They take care of themselves .