with better mobs, the zombie ai takes over with some villagers making them break windows and doors, as well as emptying chests and furnaces and causing the guards and archers to attack the villagers and each other

https://github.com/Flemmli97/ImprovedMobs/blob/26f6b2855fda99e6b7079f4428241987d56fbafb/common/src/main/java/io/github/flemmli97/improvedmobs/events/EventCalls.java#L190

I assume you mean ImprovedMobs? It assigns the stealing goals to every pathfinding entity. You can blacklist or ask the mod author to add mca as a default blacklist, but other than that I'm not sure how it is mca related.