> Why did the rules change?
I'm not a Twitter user so don't know exactly, but from what I see being discussed, it seems to me that there used to be more tolerance towards certain groups (apparently right wing, but probably others, too). But maybe that's just it, the rules themselves haven't changed, they're just more strictly enforced now (I actually don't know).
I'd say that what they're doing is obviously not illegal, or else we probably wouldn't be having this conversation because it would be much more clear-cut.
However, it's more of a "moral" issue, for lack of a better term. They advertised the platform as a medium for everybody to exchange. Now that a lot of people have gone there because of this advertisement, it has become more or less a public utility.
Now, again, I'm not saying what they're doing is illegal, they are not legally a utility, there are other avenues for people to communicate, etc.
> A country club being very popular doesn't suddenly make it a public space.
While I think you're right in the general case, I can't help but think there's a question of measure involved.
The country club will advertise exclusivity. Even if it's just for pose, and it's actually easy to gain membership, it will actively not pretend it's open to any and everybody. Also, it will require people be somewhat close geographically and will have a fairly limited reach. If the club said "we're open to everybody, we want to encourage public conversation" [0], then I'd consider it the same way I do Twitter.
Contrast this with Twitter, which explicitly advertises its openness.[0] And when you can subscribe to Twitter just by having a random browser and an internet connection, wherever you are in the world, and when pretty much anyone and their grandmother are using it to communicate, and when there's an assumption (be it misguided!) that Twitter is a public space, I think it's at least worth it to consider the question.
The answer may well be a firm "no", but it may also be "woops, this is actually something new, which we hadn't considered in our (quite old) laws. Maybe we should do something about it".
To sum it all up, I think Twitter, FB, etc are all a fairly new kind of "thing". They are private entities in that they are funded, operated, etc by a private company and with that private company's goal in mind. But their operations are clearly designed to attract the most people who then communicate on their platform.
Just as we regulated what can and can't be done by a telephone company or an electrical company (all private entities!) when those came about, I wouldn't be shocked for there to be some kind of specific regulation for those platforms, more than "just don't break any laws". It seems pretty obvious to me that trying to apply pre-existing models to them doesn't work all that well.
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[0] From about.twitter.com, emphasis mine:
> We serve the * public* conversation. That’s why it matters to us that people have a free and safe space to talk.
> We believe real change starts with conversation. Here, your voice matters. Come as you are and together we’ll do what’s right (not what’s easy) to serve the public conversation.