The forces at play when it comes to communication platforms are not so black and white. I didn't say that I expect to have the inalienable right to use the service. I just expect to have the right to use the service without especially onerous "cost" to me (such as being subjected to privacy-invading surveillance/tracking technology and advertising). If someone goes on there and spouts walls of swearing and racist memes or whatever, yeah, banned.
And, actually, have you tried just not using Facebook for a year? Don't even log in whatsoever? Try it, seriously. I have missed parties, concerts, family gatherings (seriously), news of births, marriages, new homes, major life events (including deaths). I found out my cousin had a kid like 6 months later. I found out a friend died months after it happened. I miss out on the opportunity to partake in things that would have greatly enriched my life. This is the cost to me, personally, by opting out of THE platform that EVERYONE uses. I can't just constantly SMS and call everyone I know asking them every detail of their life, because they exclusively share it all on Facebook. You simply cannot invalidate this very real cost as "yeah well, just use something else".
These huge costs of exclusion are exactly why I believe that I should have the right to access de-facto-standard communication services with software that respects my psychological stability, privacy, accessibility needs (including cognitive), of my choice -- again, as long as that software conforms with proper API usage behaviour. Right now, I'm in a pretty coercive position where I either subject to the objectively-harmful design of the Facebook platform, or face pretty adverse effects to my socialization. That's one reason case where governments enact laws, to protect individuals from these sort of extremely skewed power imbalances.
BTW, I get what you're saying. All these services are tecnically optional. I kinda used to feel that way, until I actually started not using the services that I felt were manipulating and coercing me. Then I realized just how much power these services have over us. I realized these services are optional in just the same way as the telephone and the automobile used to be. Totally still optional. Just mail a letter instead. To me it's like, at this point, as a society, we need to decide whether we care if someone can be seriously cut off from modern society because they don't agree to have advertising shoved in their face, manipulative "algorithmic feeds" selectively shown to them to "drive engagement", and unprecedented surveillance cataloguing their every action 24/7/365.