Metaverse gives access to play against the computer generated environment along with players. This will be more interesting, but how far this will be cost effective needs to be analysed. With time gambling sites have used different technology to keep them alive to the current trend. The latest being smart contract usage for the provably fair operation. Maybe the upcoming move will be towards Metaverse.
It will be cost effective if the players are willing to pay for it. But to be honest, I know several gamblers (and play a little myself) - I have never heard from them any wishes regarding gambling graphics or anything like that. For ordinary gambling, the Metaverse is unlikely to provide anything new. Maybe there will simply be some interesting opportunities like running around the field next to the players (in the game on which made a bet), of course virtually.