Given his views on software-related things, it's not particularly surprising to me that his approach toward a dis-invitation is... provocative, designed to go viral by tapping into certain aspects of a certain subset of dev culture, and not particularly well thought out.
Even if there had been a speaking fee, the conference could have fulfilled their end of the contract by paying him but not having him speak. There is no scenario under which the conference would have been forced to allow him to give a presentation.
The many spelling mistakes in this post lead me to believe that he was very, very angry when typing this up. I'd not be surprised if it was deleted by Monday.
Of course not. But that isn't my point.
My concern isn't that he would actually file a lawsuit -- that's a non-starter. My concern is that his reaction to being snubbed is to publicly threaten the conference organizers, and the other speakers at the conference. That sort of behavior suggests a hostile, combative attitude that likely goes beyond this incident. That is the bullet I'm suggesting that the conference may have dodged.
Conference asks Martin to give a presentation. No money is to change hands, no contract is signed.
Conference changes their mind and decides to not have him speak after all.
Martin's reaction is to throw around legal threats like "breech of contract" [sic] and "tortious interference"???
Sounds to me like the conference dodged a bullet.