That is not quite how it works. In fact, major science journals would review submissions and decide which ones are publishable.

Should anybody be able to publish anything, even if it is wrong or outright false, in the same platforms used to spread actual, verifiable, knowledge? I don't think so.

Science journals review articles based on the quality of their methods, not their accuracy. If I do an experiment and find neutrinos moving faster than light, it's almost certainly incorrect, but if none of the reviewers can find an actual issue with the methods, it's still very much publishable. They can't stop something from being published just because they don't like what its saying.

> They can't stop something from being published just because they don't like what its saying.

This is still not an issue with the methodology itself. Science journals do not abide to the general notion of freedom of speech.

Lots of places have restrictions on how you can say something, but still give wide berth to what ideas you can say. Just because I'm not free to express my distaste for The Last Airbender by punching M. Night Shyamalan does not mean I am not free to voice that opinion. Science journals can require your speech to be in a certain form, namely it must be science, but you are not barred from publishing anything because of what you are saying. While some institutions, like the US Federal Government, might be held to higher standards, this is what most people are referring to when talking about freedom of speech on a platform.