CapFriendly is usually on top of this stuff but they're completely missing the point here. Nashville retained $8M over two years on Johansen for nothing in return - should the Avs have given them a 1st+ due to the "market value" of that amount of retention? Hell no, because retaining that much of Johansen's salary was a prerequisite for trading him at all. Nashville avoided having to *attach* 1sts to trade Johansen at full salary.
Karlsson at full salary with no bad contracts coming back would have had negative value, not to mention the trade literally could not have been completed because no team can absorb 11.5M of cap on August 6th. The way I see it, the Sharks are getting a 1st for taking on Granlund and Hoffman's contracts. Karlsson at 10Mx4 is still an insanely risky contract so the value there is probably on par with Rutta.