It just doesn't matter if it is nft or not.
That is the point.
Nft need to be provided as well. Access to it, tools etc. Mining and verifying it is costintensive.
Ubisoft didn't just use nft it went to a company which provides a nft Blockchain. They could just go to any company for this. It's cheaper to just use a database.
Fiat currency is basically already proof of stack. Because there are so many like me having money in a bank account. Pensions etc.
Nft needs either a resource intensiv PoW or a PoS which both have not been be solved in a good and scaling and save way.
So why not using PoS in the normal world with creating a company, contracts and a basic database? It's good enough for everything we do and we know how to do it.
You don't see it now, but once many games allow you to resell the skins or game itself, and gamers get used to that, publishers that don't allow it will look evil.
Coordination between many companies is an exceptionally difficult problem without blockchains. This is what NFTs solve in a simple way - a neutral platform that every party can easily integrate with knowing the rules, API and data integrity won't change.
Before we solutionise to blockchain though we should work out how we want the world to work.
This is my main issue with discourse about NFTs and Blockchain - it gets banded around as a technical solution to solve everything before anyone has even started to think of what the requirements are for the problem we are trying to solve.
1) Does Steam want to allow you to download games to their platform when you have bought it from the lowest cost seller, when they will take zero cut of the revenue?
2) Do games sales platforms want to make it so you can leave their platform en-masse with zero friction?
3) Do developers really want to lose control of being able to revoke keys (e.g. cheaters) or lose the ability to stop the transfer of the license to other players? (i.e. block resale). And if developers / game sellers retain the ability to revoke keys as part of the design of the blockchain contract, how does that avoid the original situation where Ubisoft is revoking access to inactive accounts?
4) What does it mean if I lose access to my account in an NFT world? If someone steals my account can it be recovered? Can I get my games back?