I guess so. Been away from the states for 15 years and no one can tell where I’m from anymore. I speak Japanese and mandarin though those only invade into my English consciously. The German, Italian, Iranian, Polish, British, Israeli and west African accents that creep in are completely unconscious 😂
My last employer thought my passport was fake 🤷♂️
Yeah. Sounds like my experience, except scaled up. Still the same results.