This is racial bigotry.
These firemen are getting screwed because of their race.
Without being asked, the identities of the three real men who did this were altered to fit an unspoken, but very powerful, political theory. That liberal theory says that everything, including the most searing memories of our recent past, must be changed to serve their rigid views on inclusiveness and tolerance.
I'm amazed that they didn't change the names involved to something more ethnically diverse. Or added a woman and Musli-American. That may come when the real truth is more thoroughly suppressed.
Probably in part, but it's also aesthetics. The firemen, while brave, are not exactly pretty. The stuff most people look at and declare to be good art, is declared to be so, largely because the artist had the good sense to pretty up that which was visually flawed. The statue will not feature any pot bellies, the stances will be more "heroic" and the faces will be...well, chisled.
It is for this same reason that you will never see a statue of Janet Reno that looks like Janet Reno.
This point about individuals acting to raise the flag is right on. The problem is that our society is no longer a society of individuals - we are society of ingroups and outgroups. This whole "us and them" thing is apparently being institutionalized by the NYFD, among the countless other companies and organizations caught up in the same after wrangling the PC movement.