Huh. Exile implies they're cut off from any income, can't raise troops, etc. Effectively, an exiled noble is a nobody with absolutely no power who's been kicked out of his nation and left to his own devices. Getting taxes or having an estate - period - is completely opposite of what exile is or implies. Exile should mean what its supposed to mean, that you're cut off and need to find another realm to live in because you're getting absolutely nothing from where you were exiled from.
I don't think it works that way anymore, but I can't say for certain.
