While a good effort, it won't solve the question, because MENA isn't a color. White/brown/black/etc. is an entirely different system of racial classification than geographical delineation (European/Asian/American/MENA/etc.) or ethnic delineation (Persian/Arab/Russian/etc.).

You would need to use another color, which people did with red and yellow, and which history realized was both kind of fucked up and that there are better ways to describe them (Indigenous, Asian). Black was claimed by the people it describes and white people made up the system in the first place. It works (to an extent) because neither the group viewed as black or the group viewed as white can actually be broken down into the other categorizations. Sure, white Americans were primarily originally European, but they aren't anymore culturally or geographically. Likewise, black people were primarily originally African, but they aren't anymore culturally or geographically. Furthermore, white and black are necessary terms for discussing colorism that encompasses multiple groups and parts of groups.

White and black exist, so brown was invented to fill in the gaps, but it just... doesn't work. The groups that "brown" is used to tie together aren't tied together. South Americans, Central Americans, Middle Easterners, and Southeast Asians cannot be lumped into one category like that (not even to discuss or describe colorism, because the colorism, the history, and the impact experienced by South Americans is different from that experienced by Middle Easterners), and they fit into better ones. Most also come from parts of the world that doesn't categorize itself by colorism. This is why the whole thing breaks down.

TLDR; It'll continue to be a problem forever.