They must be doing that. I used to live on the CA coast, and as a fishing fanatic, always had ling cod fillets ready to go. I caught other species of cod, too. But when I thawed them and cooked them, water didn't come bubbling out, shrinking the size of the fillet, causing it to boil instead of quick-fry.
I'm toiling with a brand of wild-caught seafood called Simply Seafood. I have a bag of individually vacuum sealed fillets. I thaw the sealed bags in cold water, and when I cut the clear plastic open, several tablespoons of water dribble out. I pat it dry with paper towels, pressing pretty hard. But when I put them in a smoking-hot pan, the water bubbles up and boils the fillet. I hate that. It doesn't taste bad, but I know the real thing and this isn't it.
Could I pat and press the fillets as dry as possible, then lay them on 1/4 inch steel mesh, elevated, so a close fan can blow all around them to try to dry them out? I'd probably have to protect the thin areas of the meat, so the thicker parts can dry. Does this make any sense? I know about the dangers of growing slippery colonies of bacteria patches on the fillets.
I can hear it now, "Find a source of good seafood". But I live up in the sticks now. No more seafood deliveries that I know of.