Intent is always difficult to judge, unless someone has explicitly told about his - guessing about someone else's intent is a bit risky.
I agree, which is why I think we should work in a mechanic that makes these actions harmful and difficult, instead of controlling with rules.
But for this case... the guy was left with a completely nonviable realm. No possibility to make his stronghold a capital. Even if he wanted to remain ruler of those poor regions, it wouldn't have been feasible..
