Even if it is in the best interests of 80% of society, society includes the other 20% who used to be free to pick a better course of action and now are forbiddenby law.
The FCC currently decides on concerns of wireless spectrum concentration on a case-by-case basis: what's acceptable in one deal might beforbidden in another.
One of the reasons race is treated as a forbidden classification is that it demeans the dignity and worth of a person to be judged by ancestry instead of by his or her own merit and essential qualities.
For example the gleaning system by which farmers in Israel were forbidden to reap to the edge of their fields is mentioned by name as to be preserved for the benefit of the needy among the Jewish community AND the alien.