Isn't the main benefit (for the operator) of a walled garden specifically that it keeps new entrants out? Why would any of the big players let some startup NFT

Isn't the main benefit (for the operator) of a walled garden specifically that it keeps new entrants out? Why would any of the big players let some startup NFT company offer interoperable NFTs when they could just as easily do it themselves within the same user database that already exists? More generally, why would you use a blockchain for such an application at all? If some group of big gaming companies were interested in having in-game assets be transferable between their games, why not start a joint venture that manages the shared database instead of giving all the power away to some group of blockchain devs? That seems like it would have a lot of downsides (exposure to rugpulls, difficult onboarding for users that don't have a wallet yet, etc etc etc) for very little upside, and thus not a thing that company executives would be interested in.