Books
If we wish to know the force of human genius, we should read Shakespeare. If we wish to see the insignificance of human learning, we may study his commentators.
— William Hazlitt · Table Talk: Essays On Men And Manners (1821-1822)

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker draws a sharp contrast between Shakespeare's writing and the work of his commentators. One supposedly displays genius, while the other exposes the limits of learning. The balanced sentences turn praise for creative work into a cutting criticism of those explaining it.
Context reviewed