-When a realm loses its last region it should default all diplomatic stances to neutral because it's pointless to have peasants mad about foreign policy with a realm that doesn't exist. It would be like people protesting the Vietnam war in 1980 or demanding we nuke the Soviet Union. It would be even more ridiculous to ask players to spend time on diplomacy with non existent realms, that would be like present day United States having an ambassador to Yugoslavia
Actually, it makes quite sense that people keep hating the government that made previous treaty, even if they are no more. Following your example, people still protested for the Vietnam war in 1980, even now the whole thing tainted the USA irreparably.
People sometime remembers
