Having rich data types allows a lot of things without having to write your own layer. Spatial indexes are extremely efficient, and I can't query geometries effi

Having rich data types allows a lot of things without having to write your own layer. Spatial indexes are extremely efficient, and I can't query geometries efficiently when I'm storing geometries as a blob. The same goes for dates, json, XML, ranges, etc. The problem with reserving specialized logic for the application layer is that it limits you to simplistic indexing schemes and you end up doing excessive IO and filtering in memory to get what you actually want. The idea that databases shouldn't have specialized datatypes is really only an idea that works in simplistic crud apps. The world is much bigger than that.