Based on the speaker's allusions in Midsummer to Shakespeare and sonnets, readers can infer that the speaker

thinks that other authors are better than Shakespeare.

believes that Shakespeare wrote about race relations well.

is deeply familiar with Shakespeare and his works.

feels that only certain people truly understand Shakespeare.

The best answer is:

is deeply familiar with Shakespeare and his works.

Derek Walcott's allusions to works by Shakespeare, and his choice of title for the piece (a reference to Shakespeare's a Midsummer Night's Dream), show that he is deeply familiar with Shakespeare and his works. It is a stretch, however, to assume that he associates Shakespeare with race relations or that his judges people based on their knowledge of Shakespeare.