Hm. So suppose you work really hard to get a law passed that makes my relationship with my wife illegal. You don't do anything illegal while working on that—it's not illegal to try to get a law passed. It's perfectly legal for you to argue in favor of making my relationship with my wife illegal. Now suppose I later decide not to hire you when you apply for a job at the company I run. Are you seriously arguing that in so doing, I have curtailed your freedom of speech?
Now, suppose I owned an ISP, and you wanted to do your organizing to pass a law to make my relationship with my wife illegal using the connection that you get from my company. And suppose I found out, and prevented you from doing so. And so I canceled your internet connection, preventing you from exercising your freedom of speech. I really have curtailed your freedom of speech here, haven't I?
So if you are arguing that both of these cases are a curtailment of your freedom of speech, I think you're out to lunch. If you're arguing that the latter is, I'll give you that, although I think you will find that the law at the moment is not on your side. But that's why it makes sense to treat internet service as a regulated utility: so that you can have free speech rights there, where I think we can all agree you should have them, even if I don't agree with what you might do with them.