Arjen made a pretty good list to start with. It’s just a problem the Oscars (and many award shows) have always had. It’s becoming more glaring over the years as we’ve heard more public discussion about it. (“We” meaning white people - POC have seen it from the start.)
To add to Arjen’s list, there are several great performances in Parasite, I previously listed Ana de Armas, and Taika gave a great performance in Jojo Rabbit. Plus, I’ve heard great things about Queen & Slim. I’m sure there’s more I’m not thinking of right now.
Plus, of the actors who actually were nominated, I’d imagine only a few were as deserving as, say, Ana de Armas or some of the others.