Elder millennial here, my T.V. often has subtitles on, but that’s because I only speak English but frequently watch content in other languages, namely Hindi, Spanish, Tamil & Telegu, and it’s still on when I do watch something in English.

That being said I turn the English off as soon as I find the remote, and one of the things I least like about visiting my brother is his wife insists on having English subtitles in large font all the time. Particularly annoying when watching something live like hockey.