Disclaimer: This Bug is related to MC-140973, the difference here is that this Issue is aimed to match Villager Spawning with Beds, unlike MC-140973 where this issue is aimed to match Villager spawning with Doors, since 19w11a with the new Villager AI the Houses of the Villagers are now determined by Beds and not Doors anymore.

 
Note: I will not be counting Proffession Houses, only Small, Medium and Big Houses because Proffession Buildings seems to only be designed for the Work Schedule and not for the Sleeping Schedule of Villagers.

With the introduction of new the Villager AI in 19w11a, sleeping is now a very important activity of Villagers and the amount of Beds should determinate the amount of Villagers, basically meaning that for each Bed generated, there has to be a villager, but that's the exception in some Village Structures because the Villager spawning is determinated by the number of Jigsaw Blocks. Which are missing in some Houses leading to sometimes find Houses empty of Villagers.

 
Besides highlight the issues I will also provide solutions to these problems.

Snowy Village

- Small House #8

snowy_small_house_8.nbt

There's a missing Jigsaw Block that grants the spawning of a Villager here.

Solution: Add the missing Jigsaw Block back and then save the Structure again.

Desert Village

- Medium House #1

desert_medium_house_1.nbt

This Structure generates with 2 Beds, but there's only 1 Jigsaw Block that spawns a Villager, meaning one Jigsaw Block is missing for the other Bed.

Side issue The current Jigsaw Block turns into Air instead of Smooth Sandstone, leaving a hole inside this Structure after spawn a Villager.

Solutions: Include another Jigsaw Block that spawns a second Villager for the other Bed and make sure both Jigsaw Blocks turns into Smooth Sandstone.

Taiga Village

- Medium House #1

taiga_medium_house_1.nbt

Just like the Desert Medium House #1, this Structure includes 2 Beds but only 1 Jigsaw Block generates and only let the spawn of a single Villager.

Solution: Add the missing Jigsaw Block set for a Villager spawning.

- Medium House #3

taiga_medium_house_3.nbt

Missing 2 Jigsaw Blocks with Villager spawning for both Beds.

Solution: Add the 2 Jigsaw Blocks that are missing, close to each Bed.

- Medium House #4

taiga_medium_house_4.nbt

Missing 2 Jigsaw Blocks with Villager spawning for both Beds.

Solution: Include the 2 Jigsaw Blocks that are missing, close to each Bed.