If there would be lower amount of cases, there would be less skins thus the price of skins would go up
I think it would have the same minimal affect on the marketplace as it did for TF2. During the Crate Depression, Valve came up with the solution of making the bugged items untradable/unmarketable, and offered refunds for the keys used during the exploit. The items wouldn't be tradable for 7 days after their unbox, so it would only affect the Steam Market if anything. Prices might crash for certain coverts briefly, but it wouldn't last long term.