you are right, ignore them. but banning the event is not a solution.
I would ban people on a private system if they are causing a problem with the service. If I were running the service then the criteria I would use is whether or not it's impacting how I run the service. Probably to your horror, I would think very hard about banning people who I don't personally want to attract and who are chasing away the people who I do want to attract. As much as possible I would avoid it, but a big part of running a good establishment is choosing your clientele. It is analogous to refusing to serve someone who is loud and beligerent in a find dining establishment, while encouraging that person in a raucous bar.
I feel that people should be able to say whatever they want in their own homes. They should be able to say whatever they want in their own establishments. They should be able to publish what they want and sell/give it away to people who want it.
However, I think there are limits to what should be accepted in public spaces. I think that people should not be forced to publish things they disagree with, unless they have a monopoly or near-monopoly for publishing in a medium. Controversially, I think that people should be allowed to refuse service for any reason, unless they have a monopoly or near-monopoly on the service (and I happen to live in a country where this is the case).
So, that's my opinion. Believe it or not, I'm not actually interested in debating it, but because you asked me what my opinion was, I gave it to you. I suspect it differs substantially in some ways from your opinion and I have absolutely no problem with that.
Think what bothers me most these days is people cheering for censorship just because it's currently being used against people they don't like without thinking ahead that one day the power structure could shift and the same powers could be used against them.
There may be a small problem with that. It is easy for people to keep making the same arguments over and over and over again. You will get tired of coming up with counter-arguments. Eventually you will quit, and they will be the only people talking.
It is especially difficult if the other person chooses their argument so that it is easy to say, but difficult to explain why it is wrong. An example might be: Eating eggs is unhealthy because there is a lot of fat. It's an easy argument to make and defend, but it is too simple to be true. Eating eggs can be very healthy in many circumstances, but to explain why requires a lot of technical explanation.
Usually people will prepare ways to defend their argument. For example, they will collect a list of papers that show that eating fat is unhealthy. It's easy to find hundreds of them. If you say, "We need to eat some fat", then they can list a hundred papers and say, "You have to argue against all of these papers". Of course it is impossible.
Because of this, it is often best to avoid discussing things with people who have no intention of listening to you.