having a cursor controlled by a joystick would make looting very slow

Perhaps, but aim down sights allowed for controllers to toggle two different sets of aiming speeds on demand, and Destiny-style cursors allowed for fast inventory management on character equipment screens that typically only worked on a mouse. There’s probably a way to do it that’s a little bit different than just mapping a mouse cursor to an analog stick that requires devs to be a bit more clever about it. The wildest one to me is that Baldur’s Gate 3 looks entirely different when using a mouse and keyboard as opposed to using a controller. The likes of Elder Scrolls come up with one UI that can be controlled with either device, but even if I think that UI works great in both realms, people who’ve been playing those games for 20 years have a certain expectation for how it should look and work.