Free ad-supported European platforms would probably be acceptable. The issues are:
1) The EU would probably reject US-style moderation. They don't have the same level of tolerance for speech they disagree with. HN is up to what, its 3rd public moderator? The EU would probably have some sort of law that there must be some maximum number of mods per user if they had big social platforms. What if right-wingers say something without a mod looking over it? Europeans wouldn't stand for that sort of laxity or dang's obvious moderate bias.
2) The ad-supported aspect is likely to be problematic in the EU. The regulators seem pretty suspicious of that sort of thing.
3) A lot of the interesting people who were in Europe seem to get brain-drained to the US. Most of the interesting Europeans I know are US citizens because in the US they get paid well.
That's a lot of assumptions about what the EU would do. It's also a bit rich to hold the US up as a model of free speech at a time when liberal views are being actively censured.
As for the "most interesting Europeans are Americans" thing, that's such a strange statement that I'm not sure how to respond, other than that has not been my experience.
I don't think it's a lot of assumptions at all. You hear people decrying ad-supported websites all the time. When pressed on the issue they essentially resort to "well maybe these websites shouldn't exist then!", which isn't a solution.
You also hear a lot of Europeans cry out for censorship. They just think their kind of censorship will leave them alone. Until it doesn't. But they don't have to worry about it, since they're on American platforms anyway.
Hacker News is available in Europe, it doesn't even have (or need) a cookie banner. There is nothing here that would raise any eyebrows. Americans seem to misunderstand how "non-free" speech is in Europe. It is mostly calls for violence, libel, and some historical oddities (holocaust denial in Germany) that are not allowed in public.
1. As much as I dislike the thought of law mandated overzealous moderation, you're probably right.
On the other hand, if doing this will let us avoid another genocide [1] maybe it's worth it.
2. We're concerned about privacy, but ad supported businesses are as popular as everywhere else (just regulated a bit more strictly). There's probably more fear of processing too much personal data and being sued, but it's good in my opinion as a customer.
3. Also true. But, assuming you're American, isn't the selection of Europeans your know biased? Anecdotally, most of the interesting Europeans I know are not American :).
[1] https://erinkissane.com/meta-in-myanmar-part-i-the-setup
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