Legally obligating each studio to run a centralized service for license verification would be no better than requiring the publishers/distributors to run such license-verification services; in both cases, the backends would die with the economic actor.
The nice thing about an NFT (per se, a deed), is that you still own it, and it still has legal effect, even after the entity that originally created it ceases to exist. A distributed ledger will remember that Ubisoft granted you an IP license for X, even after Ubisoft stops existing as such, with all their assets sold off or lost. And any games built to check that distributed ledger, will continue to find your license there, and start up just fine.
But those games are running on hardware that you control. You therefore also control what version of the ledger the games can observe, and you can choose to show it an old version or a fork that has been mined with a tiny amount of PoW, so things like activation counters wouldn't actually give you the guarantees you are claiming. Perhaps for online gaming, the peers could require proof of ownership via the central ledger. But I would imagine that everyone would just apply a crack to disable those checks, because spending crypto fees whenever you join a server just to protect the IP rights of a defunct company is such an overkill solution, and frankly I find the use case highly contrived. I don't think it is realistic to assume that gamers will accept that what used to be a simple license check now involves downloading and verifying gigabytes of ledger history.
Just use off-ledger verifiable receipts. If Ubisoft goes under and sells off its IP, then the buyer should be legally obliged to run a similar ownership service with the digital receipt being the proof of ownership OR release the games to public domain without license checks.
The nice thing about an NFT (per se, a deed), is that you still own it, and it still has legal effect, even after the entity that originally created it ceases to exist. A distributed ledger will remember that Ubisoft granted you an IP license for X, even after Ubisoft stops existing as such, with all their assets sold off or lost. And any games built to check that distributed ledger, will continue to find your license there, and start up just fine.