I think you are misreading it. He closed a $450 million deal to sell half his company. I think he knew exactly what he was doing. Besides, he could use the write-off.
His big loss proves he DIDN'T know what he doing. He got in very late. What an idiot! RobinHood restricting accounts to only close positions should not have effected him not in the least if he was in $50/share. There was plenty of time for him to get out with a profit... UNLESS HE GOT IN WAY, WAY TOO HIGH. IDIOT!@