Bethesda actually started doing this in Fallout 4.Game uses teleport to move stuff around, I seen it yesterday by chance. I was using See Star Stuff ability on my ship (that lets me see through walls) and I noticed how suddenly one of my companions teleported from same deck I was on through walls to deck above me LOL
They do same shit with ships but hide it with that short animation of travelling and short fade to black.
It helps keep the companions close, but I find it incredibly jarring, as it violates all manner of rules around object permanence.
You'll go into a dungeon, sneak around, and your companion gets "lost"... then you'll round a corner and your companion just comes out of a room there is no way for them to get into nor they have any business being inside of.
Another I've found immensely jarring was just running around on the overworld.
I'll turn around to see how my companion is keeping up, and I'll see them running/sprint in the distance,
Then I'll turn back to face the front and keep running, only to have a panic attack: the companion teleported right in front of me, and I shot them in the face because I mistook them for a raider.
I have no idea what Bethesda was thinking... it's the worst band-aid you could put on companion AI and pathfinding being utter garbage.
I much prefer the way Skyrim mods alleviate the pathfinding issue: Give them a temporary buff of super speed.
It looks silly, but at least you can see them move from A to B, and not just magically warp to places that make no logical sense.