Villagers will not pathfind out of water that is two or more blocks deep.

To recreate this bug, create a pit that is two or more blocks deep, fill it with water, and spawn villagers in the water or let them fall in on their own. Even a 1x1 hole filled with water that is two or more blocks deep should recreate this effect. Villagers will not even recognize workstations placed nearby.

Multiple villagers will sometimes bump each other out of the water, but a single villager will almost never escape. Villagers will pathfind out of water that is one block deep just fine. They seem to be basing their pathfinding off of the bottom of the pit, and ignoring the fact that they can swim.