And I think the situation is similar for other US-based social media sites such as Twitter.

But, this list could very easily grow. There are almost 200 countries in the world, and about one-third of those are authoritarian regimes, and at least another third could be classified as semi-authoritarian. That's a lot of countries which might be inclined to ban US social media and could do so in the future.

I think China could export its own social media services to authoritarian and semi-authoritarian governments in other parts of the world – a lot of those governments would be very interested in social media offerings with built-in tools to enable censorship and information manipulation.