Sterlings treatment was totally different imo. He left lfc 2015, the hate started in May 2015 from lfc pundits who started painting him as greedy etc for leaving lfc. That hate continued in the press and went into him being a gangster with gun tattoos and many children to many wives, taking many drugs and going to many parties (IE the impression that many people now have of him) . That resulted in the racist attack on him from an opposition fan (Didnt stop the media hate) and then the attack from the chelsea fans at that game (Which helped to raise the issue)
Misinformation, hate, tribalism, bias (And even out and out closet racism) are all our media do nowadays. There are lfc reporters dedicated to pumping out negative City news, and I am sure it is the same with Utd players, but this situation (With Greenwood) is nowhere near (Yet) the treatment that Sterling got for the last 4 years.