Sorry if this has been reported already but the bug tracker wouldn’t let me search.
I tested spawning zombie villagers in different biomes that should have different variations (video below) and in every biome, only the plains zombie villager spawned in. The same is true with natural spawning zombie villagers. I tested older patches as well, so I think this bug came in during 1.21.9, as that patch had the same problem but 1.21.8 didn’t.
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We're tracking this issue in MC-302516, so this ticket is being resolved and linked as a duplicate.
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