> The official reason was that a lot of browsers defaulted to en-US maybe browser should default to sending no value or a special "default" value for Accept-La

> The official reason was that a lot of browsers defaulted to en-US maybe browser should default to sending no value or a special "default" value for Accept-Language. So that sites can use location if it is the default, but if you explicitly configure your browser to use en-US, then it will respect that.