There are many more meanings of right. I think the type of right that most Americans refer to when they say free speech is a right is that certain rights were (according the American ethos) granted by God (or the universe, or some similarly powerful force) and cannot be legitimately limited by government because the being (or force) that created them is not subject to governmental restrictions.
In other words, rights are granted by government. Instead, they supersede government.
My understanding is similar to this.
When creating these rights, they examined what rights could not be taken away naturally, or those that would need excessive force, perhaps even death, to actually take away. The only limitation then would be fear of punishment so that people would limit the right themselves, rather than the right to actually be able to enforce these to be taken away.
First Amendment. Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
A government cannot stop the way someone believes or has faith. They can dictate, they can try to suppress, but ultimately it is something that is found within one's mind. In the same way, one can speak whatever they want. Even if they have their tongue cut out, there is still other ways to portray what they want to say. In the same way, unless one has someone literally bound and controlled so they have no control over their body, they can write whatever they want as long as they are literate. People can assemble, even if in small groups in a limited area, even in a prison or other area without being able to be stopped fully. You could have an army to try to outnumber the citizens, but without extreme force, stopping them from gathering is nigh impossible. Even in China where they have had rules against gathering at times, people still assembled together (thought the consequences were dire in some instances, such as tiananmen square).
However, government can try to install fear to stop people from doing these things. They can do all manner of punishments, force, and other things to try to stop them. In this way, if they have enough force, in theory, they could stop people from practicing these things.
Thus I see the First Amendment as protecting these rights so that people can practice them without fear of recrimination.
Some of these are framed in a different manner in the Declaration of Independence
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.--That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, --That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness.
Most falling under the idea of Liberty, a man already is alive and has their life, though it can be deprived from them of Government, they also have the ability to be happy, regardless of what is dictated to them (though a government can try to make one unhappy). In regards to Liberty, there are things one can do (thoughts for example) that a government cannot stop directly, only through fear or control can they attempt to control what one actually thinks...etc.
In the same light, the US Constitution is attempting to protect these rights, to guarantee these rights so that people can openly show and practice them without fear.
Not ALL nations share these ideas or laws regarding the protection of these rights in the same manner.
That said, in relation to OA, it is still under the control of WotC. They, as a corporate entity, also have certain freedoms and rights pertaining to the control of various materials. In this, if we are free to voice our opinions to them while in the US (though it can be limited, for example, on ENworld, this is the property of those who own and control ENworld and thus, they have the right to control what is said or not said on their own property, there is no guarantee of free speech here. In addition, I do not think it falls under the US laws and is actually under UK or European law). Outside the US, it depends on the nation. We may still be able to voice what we want but there may be legal considerations to think about (such as laws that would get one jailed if they say the wrong things).
WotC on the otherhand is under no duress (legally) to actually listen to any of us or anyone beyond their own individuals who control the company in the US. IF it is a situation that occurs in Canada or elsewhere, there may actually be legal repercussions in regards to how much they do or do not listen (as corporations have a different status there in regards to rights, and various laws on freedom of expression differ).