I think this article is insightful, in that it offers another perspective on how language can complicate things.
I wasn’t convinced when you gave the example of the right to free speech as a negative right, because its the right for others not to suppress your speech.
I think the document was written as “Everyone has the right to freedom of opinion and expression” Instead of: “Everyone does not have the right to suppress others of their opinions and expression” From here on out, it seemed like you drew the implicit meaning of the statement rather than what was explicitly written.
If your audience were to do that same process, they can implicitly assume that you do not support universal healthcare even if you have explicitly said so, because of the rest of the context and tone of your piece.
But you did open up a new topic, which is how can we as a society ensure universal healthcare to people by ensuring that future written laws cannot have loopholes like the one you mentioned.