Manufacturers don’t make displays under 6 inches available for purchase, with special cases (such as the iPhone Mini) being made under exclusive contracts. The best lead they have so far is to try to use displays designed for the front part of a foldable phone, but they’re yet to strike an agreement.
TIL that display manufacturers are also part of the reason why we aren’t getting small phones and why it’s probably even harder for manufacturers like Fairphone to make them.
People in the west don’t actually want them - the best selling phone every single year is the regular sized iPhone, which just happens to be basically the smallest phone on the market. In second or third spot is the iPhone Pro, which is the same size. The best selling android flagship phone every year is the regular sized Galaxy S, which is also the smallest android phone on the market - and has actually been getting smaller the last 3 years or so.
People that buy large phones are mainly in developing countries where their phone is their primary computing device. They want the bigger screen because their phone is their computer/tv as well.
OEMs are just making phones bigger because it’s easier and cheaper for them to do so, and they can charge more money the bigger the phone is. Also they just hold back features from their smaller ones in order to make people buy the bigger more expensive model.