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.
At least, Metaverse can offer a new experience using VR equipment that some gamers already use to play many games. The cost will adjust from time to time and with the newest technology, everything will be updated following the current situation. The gambling industry will change when VR equipment can be applied, which may also change the interface of the gambling industry. The smart contract will solve the problem of the fee of the transaction and with so many options now, people can choose what they want to pay for the services.
This is a controversial point in view of the fact that top monitors transmit a picture of best quality, and, for example, for me personally, a monitor is much more convenient than any VR equipment, simply because I can see well with only one eye, so VR for me means a deterioration in the picture and not an improvement.
In general, there are many different unexpected pros and cons in this area, and in order to strongly attract consumers, the Metaverse must offer something really worthwhile.