"ejecting people opens the organisers up to lawsuits from the people being ejected. How many people are willing to accept that sort of liability?"
Really? The terms and conditions for most conferences I've signed up to make it clear that the organisers are free to eject me if they see fit. What's the worst that can happen? Refunding of admission fee on a pro-rata basis?
"and please don't say that false accusations never happen, it's been very clearly proven that they do (and to be clear, I am in no way stating or implying that the people interviewed for this article are in any way misstating what actually happened)"
False accusations happen. It's a dreadful reality, and I feel deeply for anyone who's been affected by it. But it's a minority of situations, and while it's true that a false accusation can affect someone's life, so does sexual assault. Working on the assumption that accusations are false until proven true protects may be fine for a criminal justice system, but in a community it hurts a small number of innocents while harming a large number of innocents. If I sexually assault someone in a back room at a conference, without any witnesses, what do you expect law enforcement to do? What do you expect the outcome of me continuing to attend and speak at conferences to be? Is my victim ever going to be enthusiastic about showing up to any event I'm presenting at? Is anyone that my victim ever speaks to?
There's a straightforward way to avoid false accusations. Behave in a manner such that nobody believes you're capable of anything you're accused of. It turns out that people predisposed to inappropriate behaviour generally manage to creep out other people beforehand.