I'm not sure that "BlacKkKlansman" deserved to win the Oscar for Best Adapted Screenplay over "If Beale Street Could Talk" and "Can You Ever Forgive Me". Peronally, I believe there is a huge distance in quality between the writing of those films.
I think Spike Lee being overdue for an Oscar helped his chances greatly.
Spike is long overdue an Oscar (he should have got something for Do the Right Thing, Malcolm X or 25th Hour).
However, I have not yet seen BlacKkKlansman whereas I have seen If Beale Street Could Talk and Can You Ever Forgive Me, and I found both superb, particularly the former. So, although I'm not qualified to compare them to BlacKkKlansman, I'd have loved to see either win (and for what it’s worth, I'm surprised neither pic was nominated for Best Picture - I guess they didn't have the mass appeal of Bohemian Rhapsody or Black Panther).
"If Beale Street Could Talk" and "Can You Ever Forgive Me" both won some Independent Spirit Awards. I'm guessing they didn't make enough of an impact for the Academy Awards, despite both of them being amazing films.
I personally thought it was a major snub on behalf of AMPAS not to fully recognise these two films, especially If Beale Street Could Talk (in view of Barry Jenkins' pedigree and the artistry with which the film was made). I adore Can You Ever Forgive Me but I suppose it's a slightly lower-key and more dialogue-heavy film than the type of eye-catching blockbuster the Academy recognises.