Let's try an unbiased take here:
This season, Will Borgen has had very poor concrete and advanced stats, and his game score has been deeply in the negative. At a 2.7mil cap hit, he's a cap dump with negative value, though for just this season. He's a UFA whose contract ends this season.
We have a third-round pick and a sixth-round pick. Would those be enough to make a team take on a pure cap dump of 2.7mil who plays at a level below that of a replacement level player? Perhaps. So let's say that that combo for future considerations is fair value just to dump the cap hit.
Kakko is 23 years of age, RFA under team control for some three years. His cap hit is 2.4mil. His individual stats have been meh, while his concrete and advanced stats have ranged from great to excellent.
Essentially, this trade is a loss for Rangers as long as Kakko doesn't have negative value. Looking at recent RFA comparables like Tanner Jeannot and the value he fetched, I'd estimate that Kakko probably does not have negative value.
So by the information thus far, and even if Kakko merely maintains his current level of play and doesn't even take off or improve, I'd say that this is a clear loss for Rangers. They should have gotten more in return, given the information currently available.