I dunno, having seen both Hughes and Kakko play for a few years, I don't really see it as being that close.
Kakko is an excellent player, but Hughes (to this point) has typically been a noticeable level up from him.
One of the things that's often lost on these boards when talking about Hughes is that he's not as physically far along as Kakko or some other prospects. While some people view that as a concern, or a knock, I tend to view it just the opposite.
If Hughes is this good now, compared to his competition, that makes for a hell of a possibility in a few years when he's more physically mature and older.
Hughes is clearly the best player in 2019, to say nothing about 3 or 5 years down the line --- which is a big part of what you're looking for anyway when drafting (and something a lot of fans miss when looking at prospects).