Too many websites assume that everyone in Europe speaks the language of the country they live in. Another assumption is that their IP is located where they are. The only locale you should use is the one supplied by the user agent.
The nice thing about real en-US users is they live all close together, and IP location really works well for them.
There are still a lot of exceptions and pissed of people, but less than when you believe the en-US locale means what it claims. So of course, make it stupendously easy to switch languages, both locale and ip based location are wrong a lot of the time.
This is one of those things where you can't really do it right, and you just try and minimize the number of people you anger.
At least have a way to escape back to English as the Lingua Franca of the Internet.
I wonder if logged-in accounts still do that, it's incredibly lazy to think "Oh, this American user is in Iceland [just to pick a more obscure country], let's assume, instead of a traveller, that she's a dual English-Icelandic speaker! (and yes we assumed if she was in America she spoke English, not Spanish!)"
Fun times.
- Github does not allow for 'web' VSCODE to have English (if I use non-English OS locale or browser).
- Google - developer sites (API) translate it to local language. While one can chane it; for reasons unknown this reverts back if one logout and relogin. BTW, most EU devs reading developer documentation still want to read things in English, as it helps better communication with rest of the world.