Thiem was addressing the media following his victory against Pablo Cuevas on Saturday when he was told to vacate the press room to make way for Williams, who had just lost to Sofia Kenin.
The Austrian reacted by calling the move "a joke" and storming out for being treated like a junior player and he has now accused Williams of acting in a manner which neither Rafael Nadal nor Roger Federer would.
"Actually, I wasn’t angry or frustrated. Maybe for a couple of minutes or so. It is just the principle," he told Eurosport Germany.
"It doesn’t matter, if it is me who sits in there. I still made a wrong statement. I said that I am not a junior anymore. But even if a junior is in there, every player has to wait.
It is a matter of course. It also shows a bad personality in my opinion. I am 100 percent sure Federer or Nadal would never do something like that.
Thiem is preparing to face Gael Monfils in the round of 16 on Monday. On Sunday, he received the support of Roger Federer.
"Something went wrong for this to happen," said Federer. "There's always a way to go, that the one who is still in the tournament gets priority. If I would have lost today against (Leonardo Mayer) I would let him go first or decide when he wants to go to press as he's got a next match.
"I understand Dominic's frustration. For him it's just about how in the world did this happen?"