I speak fluent accent less (US) English, and spoke accent less X English when I lived there, so the only signifier of foreignness is my name usually. This contributes to feeling there is a less positive reason for this question.
Not really. English is my first language :-)
Smack! I love it.
Um, no, but thanks. I guess you missed/ignored my clarification. Very few native English speakers can do a version of English besides their own consistently accentlessly without putting a lot of work into it. That's why there are people who make very good livings training Hollywood types to do an accent for a role. That anonlibn is truly accentless in both American English and X English is impressive.