Probably a legal adviser told him that it's unlikely that the Supreme Court would take the case at this point. The appeals court's decision just refuses to lift the temporary injunction against the EO. The case goes back down to the lower district court to get a full hearing and the usual course for SCOTUS is to not take cases before they're fully litigated.
You forgot the third option: Bullshitting as usual.
A reasonable person, when faced with an issue that they don't have all of the facts on, would typically respond with something indicating that they need time to assess the issue. Trump, OTOH, always responds immediately with whatever bullshit, typically aggressive, comment that pops into his head. It's worked for him in his business dealings, but it's going to get him in continuous hot water as POTUS.