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Is it misused? A media-producing company is going to keep doing so as long as they have the money to produce. The fastest way to run out of money is to produce a product that doesn't sell. What does it matter whether the final ill-fated product (the Creator Killer) is a brand new intellectual property or the 20th sequel?
It would be different if they were sequels, then we could point to a particular instalment as the killer. But when it's the same product, it can hardly be blamed for not selling as well years later.
The toy in question is Cabbage Patch Kids.
Stories don't tell us monsters exist; we knew that already. They show us that monsters can be trademarked and milked for years.
Agree with this not being misuse. Coleco was at one time a major toy and game producer, (The Coleco Vision was one of the first legitimately good video game systems, for instance) but they made a series of bad deals and decisions around The Great Video Game Crash of 1983. The cabbage patch kids were sort of Coleco's last big hit product, so when they were initially a success they went all in them... and then collapsed when the demand did.
I see Creator Killer misused for "this was the company's only reliable product line, and when it declined the company went bankrupt". Is there another trivia item that would fit better?