Of course. Protest itself is a valuable form of speech.

But there is a difference between protest and drowning out. If people have gone to a meeting to hear the invited speaker speak, and you act to prevent them from hearing views they wish to hear, that is a form of censorship.

A heckle, a boo, a retort is not the same as trying to drown a speaker out. The former is expressing your view while the latter is preventing others from hearing speech they wish to hear.