Sigh, you are taking this too seriously. You seem too focused on "universe" vs "galaxy". Nerys Myk nailed it. I've worked with scientists in the past, plus other "educated" folks who make such generalized comments/phrases that would go against the point you are trying to say.
You are being a pedantic snob. Outside of publishing papers and giving speeches/lectures, lot of scientists and other educated professionals do make such comments that might be technically misleading, but that's how conversations go, especially to relieve stress, have fun and relaxing, rather than having a stuffy workplace.