This is a dangerous, dangerous path to go down to if you belong to any kind of enlightment inspired ideology. What kind of things were supressed the hardest? Sexual Deviancy. questioning authority. Questioning relgion. You really want this kind of society? I think maybe we can stand some antivaxxer ...
Mechanisms to form consensus does not necessarily mean rule by mob, quite the opposite. Positive consensus mechanisms can be trust in the scientific method, institutional credibility, and acceptance of reason. These mechanisms can support an enlightenment ideology, not prevent it.
"Freedom of speech" is not an accident. Enlightenment thinkers have been pondering this for 200 years and more and objections have been successfully adressed over and over again. It's as much of the type of consensus you describe as we will ever have. 'But computers' is not sufficient to just do away with it.
Make them pay a material cost: link vaccination to welfare benefits/family tax rebates, works well in Australia (search no jab, no pay). Also make an up to date vaccination record a requirement for enrolment into schools.
They will complain and might keep on spouting shit, but at the cost of ~$10k/child/year they'll change their actions pretty quick.
So, you're saying this mechanism is a good thing? Because mechanisms that reinforce the current social consensus, whatever it might be for that era, tend to maintain the status quo. And a desire to maintaining the status quo is a big chunk of the philosophy of, yep, that's right, ... conservatives.
I've often said progressives aren't liberals because they don't agree with liberal philosophical values of the Enlightenment. Their "maintain the current societal consensus" argument is the strongest evidence of that yet.
And throughout history people lived to be 30 and died of plague wallowing in their own excrement thinking the devil did it.
If your ideology needs thought control to work it needs to be taken out at the back of the sheds and shot. The second a society stops discussing ideas openly is the second it starts sliding towards a new dark age.
Through all of mankind we had strong mechanisms to form consensus, including social repercussions. Those don't work anymore, since what would have become outcasts in earlier generations can now easily (for example on facebook) find like-minded communities and fulfill their social needs/get approval/etc. It'll be interesting in how different realities people can believe in before society breaks apart. I'd prefer we wont let that happen.
The question is what actually works. Censoring them might reinforce their believe, but I can accept giving up on some if it does effectively stops the spread.