It was 100% made to sell toys. Whether or not the toys were on the shelf before the show aired is irrelevant.
From the success of Star Wars' toy line until the mid-90s (mostly Cartoon Network's "What a Cartoon!"), cartoons were made and cancelled based on their ability to sell toys. Fuck ad space. Want to guess what kind of ads ran during cartoons of that time?
It's why almost every cartoon was an ensemble of characters with a monster/ally-of-the-week. "Easier" to sell a new doll than the same one again or a variant (Batman Returns really pushed the variant angle into wtf territory).
They made a show to push the boy version of Polly Pocket. They made shows based on popular videos games, but retooled iconic features just so they'd translate easier to toys.
It was toys all the way down.