وفيه نظر
There is a difficulty in that interpretation.
Bare opposition cannot itself be treated as an ordinary, literally shared property between the two compared terms. The figurative device calls for closer interpretation.
Opposed traits do not become identical: bravery is not cowardice, and generosity is not miserliness. The ironic figure instead treats opposition as standing in for correspondence and exploits the audience’s expectations.
A literal claim that a coward and a lion share courage would fail. But an utterance that visibly conflicts with the coward’s known conduct may convey humor or humiliation. Distinguishing the speaker’s rhetorical intention from the surface description resolves the apparent contradiction.