I don't know if that's your case or not, but I feel like English-speakers living in English-speaking countries dealing with only other English-speakers may never experience the misery of using Siri in other languages.

If I set it to, say, Portuguese or French, its capabilities are greatly diminished. Even simple tasks as "play a song by Pearl Jam" are impossible because Siri will try to find some Portuguese phrase that sounds remotely like "pearl jam". If I set it to English, then I can't use it to send a text to my wife (in Portuguese) or get directions to local streets (named in French). Also people's names.

Google Assistant at least allows me to tell it that I speak those other languages so if I speak in any of them, it will understand as such. I can say "play Pearl Jam" in English, "envie uma mensagem para minha esposa" in Portuguese or "trouve-moi le boulevard laurier" in French and Google Assistant will get what language I'm using. It's a big help. Not perfect, but at least it's usable.

EDITED: grammar