I notice this sometimes. This time I bought 1.3 Lb piece and it was fresh. It looked very thick. When cooked it was just like fatty lardy fish. I couldn’t tell if it was flesh, Is it pure fat, just high fat? I don’t know.
They sold you talapia and charged you for swordfish. Two different times, I have bought fish and wound up with mislabeled talapia. Once I took it back the next day, and there was still a pan of talapia with a sign saying catfish nuggets.
Someone did an exposed recently, I can’t remember who, on mis-identified fish at the market.
I don’t know how a consumer could possibly accept this kind of error. The two fishes are demonstrably different in appearance. Swordfish is almost exclusively cut into steaks while Tilapia is filleted. Huge difference in thickness (and color, tilapia is a whitefish and swordfish is grey on the outside and reddish/pink on the inside.
Only way this could possibly happen is if the purchaser knows absolutely nothing about seafood. Mislabeling of fish species is an issue, but not so egregious.
Swordfish, like other fatty fish, is quite fatty and oily towards the belly area. If you got a piece from only this area (and it’s quite possible; a swordfish is a big animal), then you likely got all belly fat.
I’ve had an issue with mushy fish in the past, but that was because I got ahold of a mackerel or a snapper that had been squashed in the net or in packing. I could tell when I got it home and felt the raw fish - it was squishy like it had been stomped on. Ick.
I think the most likely answer is that it had been frozen, despite being labeled as “fresh”. As I recall, fish can be called fresh even if it has been frozen, as long as the freezing wasn’t too cold, or too long.
Probably re-frozen if it’s mushy, or not kept at consistent temperature. “Fresh Frozen” can be a high quality process where fish are frozen immediately after catching and maintained at proper temperatures. If not kept frozen for too long it’s as fresh as you can get fish unless you catch it yourself. Unfortunately there’s not much quality control in place and “Fresh Frozen” isn’t a reliable label.
In the market, I just pointed to the catfish nuggets bin with the sign that said “catfish nuggets” and said Gimme a pound of nuggets. As soon as I got home, I saw that they were obviously not catfish, but I didn’t inspect them at the store. But the clerk put a sticker on the package, that said catfish nuggets, with the weight and price.
When the store labels a product, I don’t always look inside to see if that is what is in there.
The point was tilapia and swordfish, though. They are quite distinctly looking fish. Tilapia and catfish I could understand, at a glance. But mixing up tilapia and swordfish is almost like mixing up tilapia with tuna.