Since there are infinite crackpot ideas but only one Kresge Auditorium, the MIT community must make value judgments about what speakers and ideas are worthy, and which ones are not.
No institution should be compelled to provide a platform for all speakers and ideas. Some speakers and ideas are worthy of MIT, and many are not.
MIT faculty and leadership should embrace their fiduciary duty to make these hard judgments. They should grapple with what it means for speakers and ideas to be worthy, and what speech should not receive MIT legitimacy and amplification.
Instead this statement evades all of that by pretending to support all speech as long as it's legal.
But this is the key thing: Abbot was giving a talk on environmental studies, and confirmed affirmative action was not part of the talk he was giving. The push to exclude him was on the basis of something other the science of his talk.
Here's a better analogy: would it be appropriate to cancel musician'd concert because he's a flat earther? The argument that we have only one auditorium and we should allocate it to a better musician does not make sense unless there's a compelling reason to say that his musical performance abilities are affected by a belief in a flat earth.