My buddy caught a super skinny smallie like that once in the BWCA. It had a lead jig head partially protruding from it’s bunghole with the business end still stuck in the fish. Best we could tell the fish ate someones rig and slowly passed it through it’s digestive tract untill it finally got hung up at the cornhole. It probally couldn’t eat or digest food well and was starving to death.
I’d be curious how many disproportionately skinny fish we see occasionally caught have tackle lodged somewhere in it’s gut.