Sorry, but where does it say in any official steem documentation that the introduceyourself tag is only for newbies and can only be used once? Why couldn't someone come back after being away for awhile and introduce themselves again? Or why couldn't someone who has been around a long time re-introduce themselves again?
You can flag a person if you want, but honestly I think it's a waste of time to be the flag police. Focus on helping people grow, not on punishing people you don't like.
Well .. I'm trying to help the newbies, who deserve getting the appropriate exposure under that tag.