What I expected: Savanna villagers in Savannas. Tundra villagers in Tundras.
What happened instead: Plains villagers spawning in Savannas and Tundras instead.
In 19w11 this bug has been fixed in all the other biomes except Snowy biomes.
What I expected: Snow Villagers in Snowy Villages and Igloos
What happened instead: Plains villagers in Snowy Villages and Igloos
This occurs because only the
minecraft:village/plains/villager
actually has any villagers in it. The structure files were not updated for the snapshots, and thus, are converted to the plains villager by default.