Im a new member in this wikia but i have been a visitor for a while but idk if anyone else has had this theory or a discussion on it i havent seen one but i believe after the war was won the winning crystal gems on Rose's side went awol after the reality of never being able to go home set in and slowly became the corrupted monsters over the course of 5000 + years, and that is the reason why the current crystal gems(Garnet,Pearl,Amethyst,Rose/Steven) hunt them down and subdue them and contain them in bubbles bc the monsters use to be their comrades and friends. That is why they dont break theirgems bcthey hope some day they willbecome goodagain and be themselves again. Pearl said they became wrong(paraphrasing) perhaps the tragic war and being banished made them that way like ptsd(post traumatic stress disorder). In secret team pear was observing the shard seemingly hoping the shards were healing bc of Roses bubble, and it was said in Monster buddies that Rose tried to heal the monster gems and couldnt, maybe why centipeetle was fond of Steven bc she once followed Rose Quartz in war. Maybe steven will find a way to restore the monster gems to fight this new brewing war against yellow diamond and the homeworld. there has to bea reason why they seek out these monsters who are mostly away from any human life...bc they are whats left of Rose's army.