In Minecraft Java Edition, there is a mob cap mechanics where if too many mobs of a category (for example; hostile mobs) are in the same loaded chunks, then new mobs of that category wouldn't be able to spawn within your loaded chunks. Although the amount of chunks you have loaded, and whether or not you're in multiplayer (where multiple people's loaded chunks could be loaded and overlapped) will affect your mob cap, your typical mob cap in a singleplayer world is around 70 mobs of that category type.
Within the loaded chunks around the 70 mobs, no hostile mobs should spawn in around that range, but while you're outside of that area and only have the surrounding area loaded in, I would recommend having some more iron golems spread throughout the village.
Edit: removed misinformation about name-tagged monsters counting towards the mob cap