This just isn't true: these people already have power. When bad ideas already have a following, attempting to silence them isn't denying them power but reenforcing it as silencing becomes a rallying cry.
Bad ideas fall to reasoned debate. Bad ideas thrive when they inherently have a subconscious or emotional appeal and are allowed to spread in isolated communities and are never challenged in open forums. Denying them platforms isn't going to stop the spread of these ideas (the internet is still a thing). It just passes up on another opportunity to challenge those ideas head on and gives the charlatans another instance of suppression to use as a rallying cry.
Perhaps what students should insist on is instead of giving them an open platform to speak, invite them to a debate. Force them to defend their ideas under harsh scrutiny.