re: Who is the most over rated superstar in the NBA?

Young has a better career assist to turnover ratio than Steph Curry and Russell Westbrook, while averaging more combined points and assists than both. The volume on points and assists is astronomical. When a player is doing that much, there's more leeway on turnovers. E.g., Caitlin Clark. She averaged more turnovers this past season than Young did, and averaged more over her college career than Young has in the NBA.
If you want to argue that he's doing too much with the Hawks, and that roster changes would be beneficial for the team, I'd agree.
In building rosters, you're looking for "star systems" rather than a single star. The whole premise of the thread is flawed.
Whether you want to classify him as a star, superstar, supernova, protostar, pulsar, neutron star, or something else, that's just a matter of parameters/definitions.
With no parameters in place, I take the rating to be in relation to public perception. In that sense, I don't think Young is generally considered a superstar. Although, the offensive numbers are up there. The defense isn't up there with the offense, but he still has room to improve. He only played one season in college. He's still a young player.