I play in a singleplayer survival world
Villagers that despawn are tagged and have names, but still despawn.
I can confirm this happening to me as well (Bedrock - v.1.17.2).
This is really annoying, a waste of time to return to your original position and could even cause you to loose your progress.
Imagine loosing your elytra and enchanted gear because of this.
Please release something to fix this issue as there is no incentive to play the game in this state