I don't think this contradicts what I've said. One can conclude from this statement both that Merkel believes Twitter needs to be regulated, and that the US needs stronger speech regulation in general. (also I'll note that what Twitter did isn't actually illegal in Germany, there's no law that compels social media companies to host people)
The primary message from all of these governments is that the platforms are out of line.
Your original comment was in support of/elaborating on "It would be governmental overreach [to set the rules]." That original comment had an overly permissive rule in place of what I've bracketed, but that's beside the point since all of these governments are specifically objecting that the recent actions are problematically restrictive.
> The primary message from all of these governments is that the platforms are out of line.
Yes, and one reason for that, as stated by Merkel, is that the US doesn't have a democratic framework for managing hate speech. Because such a framework is illegal under the first amendment. And her statement suggests that the US adopt a more German framework for adjudicating such speech, so that corporations don't need to make their own rules.
Your claim is that Twitter is "effectively" acting as the government. That's not true under a significant amount of law and precedent. (There are cases where private entities are acting as a government, and importantly, trying to use government force to suppress speech, Marsh v. Alabama).
In fact, one could argue that by censoring speech, Twitter is explicitly not acting like the government, because Twitter is taking action the government cannot.
