You cannot pick block a sleeping villager to get a villager spawn egg. Instead you just get the bed.
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Thank you for letting me know 🙂! I appreciate it because that way I am not left scratching my head by another "Dupe of MC-X" comment when it seems unrelated.
You actually can! It just has a really small hitbox though (at its head), and that's the bug. We're tracking this issue as MC-148559.