I respectfully disagree. Trump is many things, but naïve is not one of them. He knows what he’s doing. He’s a winner and wants to win this November and in 2020 (hint: it won’t be at the expense of the Second Amendment).
If bump-fire stocks are being banned, then it is, by definition.
I just see Mr. Trump's understanding of the RKBA is not as deep as we'd like. One cannot be the master of all things. Just because something is frivolous doesn't validate it's being abolished.