OK so the gaming industry is slow but I don't think it's that slow play to earn is probably something that'll take a while to come out, most mmo games ban you from selling stuff anyway in their terms (I think it requires extra licensing).
Yep, majority of AAA mmo games like World of Warcraft ban you from selling in-game stuff and services for RL money, but market for that is huge and is not really stopped by that restriction as people do it anyway, so there is a huge demand for a proper play to earn system.
It's true that things are moving somewhat slow; Steam recently banned all crypto/NFT games from their platform, in fear since CS:GO skin gambling fiasco, but on the other hand Epic (another major game developer and publisher) is "open to games that support cryptocurrency or blockchain-based assets" on their upcoming store so things are moving nevertheless. Good example of promising use of NFT is Gold Fever, survival/MMO PC game built on the latest Unreal 5 engine.
As an old school gamer who always liked economy part of the game, I must say that I am really looking forward to day where you can legally made serious money while playing proper games (unlike that Alien Worlds crap) without breaking TOS or competing at the highest e-sport level.