Because in the situation you are describing, when someone has lost their citizenship because they left the country, they’re not going to be eligible for the Presidency anyway so it becomes a non-issue.
That is a dodge of the question.
I can stay out of the country for the first 21 years of my life, and still be eligible to be President. These statute based citizens cannot do that.
Clearly there is something different about the sort of citizen I am versus the sort of citizen they are. My citizenship does not have conditions, but theirs does.
How can they be the same thing with such an obvious disparity of outcome?