Well, some do. Mr. Kathira and I were like bunny rabbits when we were young - i.e. the ages of Barry and Iris. Maybe not every day, but I would expect a young, healthy couple to be doing it at least once a week. Barry and Iris seem to be oddly disconnected for people who are supposed to be soulmates. I get that showing their home life, regular dinners, Netflix and chill, etc. would be boring, but the result is that they don't seem much like a couple. Maybe it is the Siri factor, but they haven't seemed terribly loved up for a while.