It's not a problem, but it does send a signal--probably one that is a slight benefit as an adult in a technical line of work, but it might send a different signal for let's say, a teenager who is already struggling to fit in with peers. It may be a stereotype, but stereotypes exist regardless of how easy you or me think it is to register a domain. Sure someone could follow just a few simple steps found on the internet, but why does that person even care to?

Although, teenagers exchanging email addresses has fallen out of style recently in exchange for sharing Discord tags or Snapchat usernames/showing snapcodes.