There was a point in time that this was the case. It stopped being so some time ago.
There reaches a flashpoint in these things where the franchise that is being exploited becomes too damaged to sustain merchandising. Star Wars. a
vastly more powerful brand, started a steep decline in 2016 in this regard and is now an economic non-starter because of how the franchise was handled. Shelves and back areas full of unsold Star Wars Merch is now a widely documented occurence, and so much of it remained unsold for so long that they started destroying it to liquidate old stock.
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Masters of the Universe had nowhere near this level of market penetration, and even a moderate fandom pull-out will effectively kill sales.