The issue I am having is that in my Peaceful Survival World, I have a pre-existing village that I had in 1.13.2. When I played Pre-release 5, the look of the village stayed the same from 1.13.2, with the new 1.14 block textures being the only difference.
If this is not a bug, the look of pre-existing villages should change with the new update.
It is intended behavior for chunks that are already generated. They will stay the same, you can delete the specific chunks and have them reload with an updated village.