Well, if you're proposing we get rid of racial classifications in the Census altogether, then the point would become moot, wouldn't it?
I'm skeptical of polling, because you have to take into account how the sample size is being attained as well as who is sponsoring / paying for the poll. I don't believe in constructing public policy via popularity contest.
Even if the MENA option is provided on Census forms and only a sliver of people with Middle Eastern or North African heritage select the option, then what is the harm?