will i be judged or will people think i'm cool if i learn to talk "oldtimey"?

Yeah. If you're into it, do it. Never turn down a chance to learn something or develop a skill. Pick your audience when using a skill though. You may be able to juggle 5 balls, but a funeral probably isn't the place. Talking like a dude that stepped out of a time machine could be cool in a bar, but not so much if you're giving a presentation on finance.