Absolute rubbish about drag. In a fixed gear aircraft it is pointless stopping the rotation. In basic retractables that do not brake automatically you do it to stop the gyroscopic effect as the wheels go up, think of the way a main gear retracts and how a force acts on a gyroscope, perpendicular and 90deg in plane of rotaton, or something like that. So every time you put a rotating wheel up it produces a twisting force that the leg is not designed to take over and over.
On large aircraft, such as an A330, if you have an inop brake on one main wheel you have to leave the wheels down for two minutes after take off so as to allow the rotation to stop. There is a lot of rotating mass just after take off so the twisting on the leg would be quite large. If the brakes are working they stop rotaton on selecting gea up.