There will always be broken people with pathologies like sociopathy or narcissism that wouldn’t agree [...]
And dismissing their way of perceiving the world is a choice which we make, not an objective mandate or imperative. We do it because the benefits to us ("normal people") seem to outweight the loses.
[...] at least if they had the rights and freedoms to express themselves and the education to understand and not be brainwashed
And how do you determine who falls in this category? Again, by a set of parameters which we've chosen.
[...] nonsensical since it destroys meaning itself [...]
Which is a judgement call you've externalized, again not an objective reality. You have chosen to believe that meaning is important, that self-destruction is bad. There's nothing in the universe that inherently holds this as being true. Whether one person or one billion people choose to believe something as true has no bearing on whether or not it is actually true.
You cannot argue for the elimination of meaning without using meaning itself, and after the fact it would have shown that your arguments were meaningless
You needn't argue for the elimination of meaning, because meaning isn't a substance present in reality - it's a value we ascribe to things and thoughts.