You can also scrub the layer’s position values in the timeline.
Or are you thinking about value graphs? You can drag those in AE in the timeline, but for position, you need to tie each position axis to a null, then move each null’s value graph.
Sorry, AE isn’t a real 3D app. It’s a compositing app that has grown, bit by bit, into a motion graphics app. Now it is a compositing and motion graphics app, but the flat layers now reside in 3D space. There are many limitations to AE’s 3D-ness.
Steve