This is not suppression of free speech, it's counter-speech. And if you've ever seen one of these guys in action on a quad, they're not remotely interested in a dialog -- they're windup toys with a script and no matter what you ask them or say to them they take one beat and just move on to the next bullet point.
The genius of this response is it's a hoist by one's own petard. These guys wrap their twisted hatred in a protective shield of religion and rely on the political correctness of never directly engaging someone on their religious convictions to get a free harangue in. The singers deftly refuted his whole shtick without anything aggressive or even impolite. If the face of hatred cross-dressing as religion, they sang love backed by real faith.
Pretty sure that's what the whole Christian thing is all about.
The other thing that's important here is this was JMU. It's fairly silly and pathetic to see these guys strutting their stupid on a top level campus because you know the kids are just rolling their eyes and on their way to something that matters. JMU's student body is the kind of place where the Campus Crusade for Christ is ten times larger than the honor roll. The kids who go there are the opposite of Ivory Tower, they're tomorrow's business school B students. When even those guys have had enough of pseudo-faithful prejudice, the game's over.
If you want to get your knickers in a twist over university intolerance and first amendment violation, stick to controversial lecturers being canceled. That's a legitimate concern and whenever it happens (which BTW is not often at all) I'm right there with you calling BS on it.