Genuinely curious if this could ever be a possibility one way or the other. Feel like it would be very popular. But it will probably never happen

It is impossible for a casino to operate sustainably with 0% house edge. Everything costs money even from a decentralized type of casino. Nothing will continue to work without money. Not to mention that money is also needed to keep the casinos from being protected otherwise casinos would be vulnerable and easy to breach into.
Not impossible since some casino offer no house edge in the past while they rely most of there win when player losing due to greed and human error on the game.
However, most of casino games nowadays is controlled by 3rd party including slots, live games and sportsbook so casino has no control the house edge/RTP set on each game by the provider.