I mean... they've given up nothing here. Mid pick, propably another they could've gotten for Borgen.
It's worth a shot. Kakko should be motivated and he has been badly mismanaged by the Rangers so who knows if there is actually something there when you give him a shot. As for his development it's been actually quite ridiculous to date. They kept pushing him for top-line minutes at the age of 18 when he was nowhere near NHL-ready and kept dropping him down the line-up, but this dude has never played an AHL game. They forced top-line minutes to 18-year old and for the 5 years after that they've kept him out of the top-6. He should have played in the AHL really early in his NA career since they had the luxury to do it and had to work his way up there, rather than be handed those minutes early.
He's at the same age as McMichael who only really now is breaking out. I'd guess in a game of ''who is more likely to turn into a top-6 forward'', i'd rather pick Kakko than 2 3rd rounders but hey, they pushed the situation all the way to this where they were literally forced to take anything they can get for him before this turns into an even bigger PR nightmare.