Generally speaking, there's two ways to determine a truth, either from experimentation and results, or from first principles.
From the experimentation side of things, you have Canada, Australia, Denmark, France, Germany, India, South Africa, Sweden, New Zealand, and the United Kingdom (I'm probably missing some) where they impose restrictions on free speech while still having mostly free speech rights. You can even include the US as well, since it does have restrictions, they're just more relaxed, and seem to only be enforced if financial damage can be proven from libel.
Now very broadly looking at that list, it seems that countries that take a most speech is free (especially speech that criticizes the government and ruling class), but some speech is restricted (especially hate related speech, speech that imply violence to others, speech that targets minority groups, and diffamation and libel speech) seem to work pretty well in practice. At least, those countries have had stable social and economic environments, and seem to allow for good opportunity to its citizen and give them a good standard of living in general.
So from the experimentation side of "truth seeking", it seems to me I'm not seeing an argument for absolutely all speech should be free always no matter the circumstances or the intent of the speech.
Now, we don't have a good experiment example of "all speech goes" unfortunately. Maybe the US is the closest to it, and that seems to be causing quite a lot of social and economic instability for now at least. But I'd say it's too soon to conclude anything on that front.
The other approach to "truth seeking" would be from first principle. The theory around free speech comes from the liberal progressive thinkers of the enlightenment. So turning to them for first principle makes sense. From my research into it (and I welcome you do your own), there seem to be no winning theory around it. All agree that speech against government should be free, but how far to take other speech in other circumstances is not clear. Also debatable if the government should be free to criticize groups of citizens or not, because that can enable top down propaganda and repression, which free speech is trying to protect against. Most theory seem to recognize the "risks" with unrestricted free speech, but some believe that the benefits of free speech against authoritarianism and majority's rule is worth it, while others think it is possible to draw a line that protects against this and mitigates the risk of unrestricted free speech.
It seems some of the thinkers that are pro unrestricted free speech also assume the system provides people with an education that allows them to identify and rationalize fake and manipulative ideas and thoughts from legitimate ideas and thoughts.
So the first principle outlook also seems inconclusive in my opinion.
That personally leaves me to conclude that mostly free speech is good, and fully free speech might also be good but that's not yet been demonstrated to really know, with keeping in mind that this uncertainty about fully free speech could resolve in it being worse or better than mostly free speech.
From the experimentation side of things, you have Canada, Australia, Denmark, France, Germany, India, South Africa, Sweden, New Zealand, and the United Kingdom (I'm probably missing some) where they impose restrictions on free speech while still having mostly free speech rights. You can even include the US as well, since it does have restrictions, they're just more relaxed, and seem to only be enforced if financial damage can be proven from libel.
Now very broadly looking at that list, it seems that countries that take a most speech is free (especially speech that criticizes the government and ruling class), but some speech is restricted (especially hate related speech, speech that imply violence to others, speech that targets minority groups, and diffamation and libel speech) seem to work pretty well in practice. At least, those countries have had stable social and economic environments, and seem to allow for good opportunity to its citizen and give them a good standard of living in general.
So from the experimentation side of "truth seeking", it seems to me I'm not seeing an argument for absolutely all speech should be free always no matter the circumstances or the intent of the speech.
Now, we don't have a good experiment example of "all speech goes" unfortunately. Maybe the US is the closest to it, and that seems to be causing quite a lot of social and economic instability for now at least. But I'd say it's too soon to conclude anything on that front.
The other approach to "truth seeking" would be from first principle. The theory around free speech comes from the liberal progressive thinkers of the enlightenment. So turning to them for first principle makes sense. From my research into it (and I welcome you do your own), there seem to be no winning theory around it. All agree that speech against government should be free, but how far to take other speech in other circumstances is not clear. Also debatable if the government should be free to criticize groups of citizens or not, because that can enable top down propaganda and repression, which free speech is trying to protect against. Most theory seem to recognize the "risks" with unrestricted free speech, but some believe that the benefits of free speech against authoritarianism and majority's rule is worth it, while others think it is possible to draw a line that protects against this and mitigates the risk of unrestricted free speech.
It seems some of the thinkers that are pro unrestricted free speech also assume the system provides people with an education that allows them to identify and rationalize fake and manipulative ideas and thoughts from legitimate ideas and thoughts.
So the first principle outlook also seems inconclusive in my opinion.
That personally leaves me to conclude that mostly free speech is good, and fully free speech might also be good but that's not yet been demonstrated to really know, with keeping in mind that this uncertainty about fully free speech could resolve in it being worse or better than mostly free speech.