Why are we not building middle income apartments?

Everywhere you look inside the loop, cookie cutter luxury apartments the likes of Hanover are popping up everywhere. Their rent? Many upwards of $2k for a small 1BR. As a native Houstonian, it blows my mind anyone would spend this much on rent in this city, when not long ago you could get a nice apartment in a good area inside the loop for $750-900. Why are we not building more middle income apartments (a la $1000-1300)? Is there really that massive of an influx of high earners moving to the city? On W Dallas St alone there are like 4 new luxury high rises with 2-3 more on the way slated to open by 2023.