There is a difference between a platform (be that a website, or a government) censoring speech, and individuals opting out of certain things.

If I choose, I can view ads and I can view spam. I choose not to, just as it's perfectly fine to not follow Donald Trump on Twitter. I am making the decision about what content I view.

An entity in power making that decision for me is censoring free speech. My choosing not to see things, is not.