The EU censors Russia today and Sputnik, and the US government wants to ban TikTok. Sites like Facebook, Twitter, Reddit, etc. are tools for soft power and the management of public opinion. We know through the NSA leaks that the US security state is balls deep in all these companies and their operations, why would countries that the US is antagonistic towards and actively would like to overthrow the governments of allow those companies to operate freely in their territories? Social media platforms exist in China, but in a form that doesn't mean ceding control of public discourse to platforms owned by a hostile state (the US). I think the first step to thinking seriously about these problems is to get out of the implicit western-centric mindset that we are all conditioned into by our media and culture. The western media basically completely fails to offer accounts for why countries with antagonistic relationships to the US/EU make decisions. It encourages us to view politics through the simplistic lens of bad country does bad thing because they are bad. It does this for an obvious reason: it benefits those in power.

On the question of taking to Cuban and Venezuelan 'expats'. You have to bare in mind that these people are only representative of a certain section of their countries' populations, which is overwhelmingly speaking the very wealthy. This is also a problem with social media, is as much as the poorest sections of the populations of many countries just don't have an internet presence in anglophone world, and obviously that goes double for 'are able to live in the US/EU'. I can't speak to Venezuela because I don't know that much about it, but in the case of Cuba, the country is democratic in a deep manner that I think Americans and Europeans find hard to grasp because our experience of democracy is limited merely to the formal participation in elections every 4-5 years. For an example of how democracy functions in Cuba you could look at the recent passing of the 2022 Families Code, which entailed a mass democratic project relatively unimaginable in our bourgeois democracies and produced what is almost certainly the most progressive constitution in the world.