You do realize Stiverne started it with the death threats right? Wilder is returning the favour, as expected by anyone with a spine. Tyson also did it, constantly.
definition of irony : someone who has never fought anyone with a pulse threatening to end an opponent's life
He said he was going to claim his life in the final press conference, that's why Wilder said it after.
Burrrman has to make it to the ring first. A cardiac arrest during the ringwalk isn't that far fedged with his condition.