He basically crushed three different roles in one film. He deserved it. I did think Downey was good that year as well.
However, whats this Spike liberties yall talking about
Did black people back in the day think Spike cost him the Oscar
Spike wasn't the first choice for the movie by black people standards. Lot of brothers and sisters felt he'd take it too easy on the subject and make it nice for white people. Spike's reputation in 92 is a lot different than now.
But to answer your question, that didn't cause him the Oscar. Them giving Pacino a makeup Oscar for at least three roles is what cost him the Oscar. Pacino easily could've had one for Godfather 2 and Dog Day Afternoon and probably should've for both. Instead he got awarded for Scent of a Woman as a makeup. Much like Denzel got his makeup with Training Day. Denzel's Malcolm X is one of the best performances in history, period. Should've gotten it but didn't but he's got two now and I think he's okay with that