For example, my HG+ child would use words like disastrous, catastrophic and horrifying if someone stepped on his sandcastle at 3 years old. The other 3 year old would likely have no clue what my son was talking about. that is not an indication of social impairment on his part.

That reminded me of dd9 who, a few years ago, was tired of hanging out with another child and thought that the best way to "break up" as friends without hurting the other child's feelings was the express that it would be preferable if they were simply acquaintances rather than close friends. The other child's mom called me to say that her kiddo came home in tears about how dd had told her that they were now enemies.
After that interaction, dd actively modified her vocabulary when speaking with other children so as not to appear weird.