If you want to sell a toy at a us based big box retailer, it pretty much has to be a licensed product.
Either you are hasbro and target reserves multiple shelves for you, or you are making Disney characters into rubber ducks or sponge bob character keshis.
Beyond that, there's a pay to play option. Roblox and Mr. Beast (I assume, I do not have insider knowledge despite having worked for onr of those entities) go the pay-to-play route, paying for placement on store shelves and breaking even on sales in order to cement a brand.
If a brand operating under that model does well enough for long enough, they might graduate to the normal licensed toy model, or get bought by hasbro.
The toy isles at most big box retailers are sad. They are devoid of joy.