Whenever someone proposes a simple solution to a social or political problem that nobody can agree on, and says "It's that simple", they're marking themselves as not understanding what they're talking about while arrogantly pretending they do. It's automatically not simple or it wouldn't even be in the news. You certainly aren't the authority on it.

So you would be ok with a phone company that doesn't allow certains groups of people to make phone calls? For instance, people whose political views it doesn't agree with? Or even worse, people with certain ethnical backgrounds?

Of course now you might say, if such a phone company existed, those people who were denied service could just choose another one. But if this company would be the one dominating the market, this would mean they couldn't reach all the people they would want to anymore. This is the analogy with Facebook.