"Lots of Americans find that puzzling because we are such a casual country. In most of Latin, Germanic and other European languages, there are formal and informal pronouns one uses in addressing people."
Sorry but I believe your analysis is incorrect, WAAAY off. The familiar and formal forms of 2nd person speech have been absent from the English language for centuries. Yes, centuries. In the UK, where there is much more cultural and social rigidity and formality than in the US, the English in use has the same form of 2nd person pronouns (no familiar/formal distinction) as we have here. As someone who has mastered use of both Latin and Germanic European languages to a greater extent than most Americans do, and who and has lived in Europe, I can tell you with some confidence that there are many, many aspects of English grammar and use that, when compared to other languages, could be described as "simplified" but in any event, different with no conclusions to be drawn therefrom. Nouns have no genders. Word forms have no declensions. Word order in sentences allows for easier comprehension in English than in some other languages when word order conventions follow other patterns. What is considered polite or friendly and what is considered to not so varies considerably. Social conventions vary from country to country and not because of language nor is language necessarily a reflection of such differences.
Differences are indicative of there being differences, not anything more, in my experience and opinion. Draw no conclusions.
The most visited social media sites, the Facebooks, Twitters, TikToks, yada yada sites are as popular abroad as here.
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