Getting stuck in terrain is really typical in games. It happens occasionally in every MMO I’ve ever played and most single player games as well. I’ve had cars stuck in walls, shooters stuck in crates, a hedgehog stuck in a cave entrance, and on and on.
When it happens in ESO in the open world you can port to any friend or guildmate to move. When it happens in a pvp instance you can use the /stuck or /unstuck command or queue for a different Cyrodil or IC instance. Yes it’s annoying, but it happens.