This is a professional conference about a particular apolitical topic. If the speaker, no matter how controversial or unpopular his unrelated personal views might be, is going to stay on the topic and not bring up politics, then anyone who tries to bring politics into it is being the disruptive force, not the speaker, and that is the person who is creating an unsafe atmosphere and needs to be ejected from the conference.
> it's pretty much impossible that TypeLevel employees would be able to magically argue him out of his existing position, and it's probably equally inevitable that he would be unable to argue them into his position.
Why is it necessary for either of them to argue the other into their position?
> Are you going to have a good Thanksgiving, or are you going to get into it with your reactionary relative for the thousandth time?
I'll tell you what I wouldn't do: I certainly wouldn't demand that my reactionary relative not be permitted to attend, and if she's gracious enough to not start a fight at the dinner table I won't start one myself. If she can be polite, I can be polite.