These exist as after market accessories but are usually $200+ USD. While useful for many people, myself included, it’s still not something Apple would think most users would laud over and be willing to pay an extra $200+ for in a general price hike. That plus the fact after market options exist is enough to not warrant them being made on the iPhones for consumers.
I don’t think even Android manufacturers would do this unless the price comes way down or it’s a device designed for industrial use, such as CAT, who has developed mobile devices for construction purposes in the past.