Then why is he saying the federal minimum wage should be $10? That takes the matter out of the hands of the states and sets a floor that they have to meet. They could go higher, but not lower.
Based on Trumps later comment that States should be setting this I took his $10 comment to mean that $10 bucks in more reasonable than $15. I don’t believe he was referring to a $10 Federal minimum wage despite the way the author of the article framed the comment.