You forgot the most important thing which every web3 games have which is the source of income outside the game itself that they can use to fund the rewards to every players.
Team just use the existing token supply as rewards while they continuously drain the liquidity on exchange by dumping team tokens and “marketing/operation” tokens using holders liquidity that result to continuously dumping of the price.
A real web3 games will be sustainable if they have other source of income for the rewards that is not from the token supply.
Exactly!
A great and ancient example if one does insist on using player funds initially to create that outside source of income is the thing called Premium Bonds in the United Kingdom.
Basically a premium bond is a never-expiring lottery ticket, that until you sell/redeem it keeps on being part of the regular prize draws.
It is like a post office savings account in that the money paid for the tickets gets somehow or other "invested" but instead of everyone earning interest on what they put
itin all the interest gets put into the prize pot for the lottery-type drawings, so large prizes are available thanks to that pooling.
An entirely outside source of initial capital to build the outside source of income would be even better for players of course but the age-old example of the "premium bond" does show how it can be done from initial input of capital from the players without needing to keep "dinging" the players for more input of funds...
Of course in crypto interest rates far higher than those typical of post office savings accounts can be feasible...

And unlike premium bonds a play to earn game need not enter any "tickets" into the "drawings" for players who fail to actually play, instead the prizes can be things like monster loot drops...
The hard part still though is probably the finding of reliable things to use as the outside source of income...
-MarkM-