Anyone who advocated a national language and tried to institute the teaching of the language would be called racist.
That's hilarious because a non-racist would assume that all races are equally able to learn, read, and speak a national language. The person claiming a national language is "racist" is implying that some races are less able than others to cope with such a change, which is itself a racist belief. It is amazing to me the way this is so often glossed over and not pointed out.
This then would have the effect of raising the overall standard of living of the entire country...
I don't know about all of that, but being able to understand one another because there is a standard is how you maintain a nation long-term, without having it spilt into factions of people who see each other as different from the rest, only to become Balkanized over time.
NOTE: this is not a joke... It is a sad truth in the US today!!!
Another sad truth: political power is gained and expanded by dividing people, not by uniting them. The extreme hypersensitivity encouraged by identity politics and the obsession with group identity has two major effects. One, it encourages emotional, irrational thinking which helps prevent the sort of attention and scrutiny those in power don't want. Two, it produces division and squabbling over matters that by design cannot be resolved, creating much distraction, wasting much energy, and most of all allowing politicians to keep (and expand) power by promising to protect each group from all of the others. It's classic divide-and-conquer.
Inventing "racists" where they do not actually exist is never going to lead to the sort of color-blind society that judges people by the content of their character. "I want to be the white man's brother, not his brother-in-law", Dr. Martin Luther King, Jr.