You mean to imply that being double-taxed after your first $100k is fair and reasonable?
Thought of differently- expats expect to be able to vote, right? Is it fair and reasonable for someone who is categorically excluded from paying taxes, to be allowed to vote?
As for the theoretical 2nd house. You would pay property tax on it.
Why should someone living outside the united states, with no houses in the united states, still pay US taxes, just because they have US citizenship?
I get where you are coming from, sure there are arguments for it, but it's not like there are none against it, either.