Freedom of speech, at least as it is currently thought of, is not conducive to truth.
Now this is a hypothesis. I am not sure it is totally correct yet, but what I used to believe is totally not true.
Even after finally letting go of egalitarianism, I still had an assumption that there was something called a market place of ideas. Perhaps there is, but if there is, I can tell you it is a frightening small place. Most people in this marketplace are sellers of one particular idea, and they have no interest in collecting new ones. It is unclear how many people are legitimately buyers.
What is clear however, is that this market place of ideas is swamped by a leviathan- the market place of feels. This is much more obviously a market. Hollywood, drugs, alcohol, self-help books- somebody out there is willing to take your money and give you whatever feel you want.
The assumption I had was probably similar to the invisible hand argument in mainstream economics. Ideas that are true are more accurate, map better to reality, so people in the market place of ideas will, over time adopt the most truthful ideas.
Meanwhile the large majority merely purchase feels. A small minority explicitly believe in nonsense and yet manage to be extremely successful. Purchased feels tend to exist a substitutes for what would be authentically elicited in the process mentioned above.
And, as we have seen, academia is actively discriminating against people who have ideas. You must accept the ideology and be in one of three categories- a) a minority, b) a woman, or c) have connections. C) is increasingly female too. I think the elites may actually be having fewer male children.
Sure, you can trot out some white professor and say, see, he came from such and such po-dunk town, and he ain't connected, he doesn't believe the progressive narrative, etc... I call bullshit. Connections can be weak connections, and these guys very obviously moderate their views until they have tenure. Even with tenure, if they want their career to flourish, they continue to moderate their views. Consider the number of economists who say 'end the Fed' versus all those who have various new strategies for the Fed to try. And then consider their careers.
At best freedom of speech is a very poor approximation of what we really need, which is freedom to discover, distribute, and implement the truth. The only thing freedom of speech gets us is the merest of possibilities that the truth may be whispered in cacophony of voices.