[root_axis]

Just repeating "non-sequitur" is not an argument. If you have nothing else to add I'll just reiterate what I wrote above. It doesn't matter how popular twitter is, you don't have to use twitter and twitter isn't obligated to provide service for free.

[GoblinSlayer]

Popularity matters: https://en.wikipedia.org/wiki/Refusal_to_deal

[root_axis]

> Though in general, each business may decide with whom they wish to deal, there are some situations when a refusal to deal may be considered an unlawful anti-competitive practice, if it prevents or reduces competition in a market.

So based on your own link, "refusal to deal" has nothing to do with this situation since stifiling the posts of world leaders is not anti-competitive, in fact, it creates a competitive opportunity for platforms that might offer better service to those users.