No it doesn’t have it. That was the whole point. The examples you gave had to each build their own in-house bespoke infrastructure for this functionality. With blockchains it already exists, it’s secure and any new app or user can start using it right away.
The difference between Firebase and Ethereum+metamask isn't a significant development cost for anything beyond a toy weekend project.
The difference is only about trust.
The argument you want to make is that we shouldn't trust Firebase, they could steal our auth tokens and act on our behalf without our permission, so we need trustless decentralized solutions.
That would be a valid argument, but a hard sell to an audience that doesn't buy the premise. I'm not going to debate it.
However, it has nothing to do with the technical layer of auth which is just "prove that you know the secret" in all cases.
Either you don't understand how this works, or you're deliberately avoiding the point.
Where do you think Metamask stores your private key?
It would be trivial for Firebase to release a browser extension that used LocalStorage to store the secret, like Metamask, instead of regular web storage.
However, in blockchain it's the combo of your private key to sign your wallet, along with the consensus engine where decentralized voting decides to accept the generation and association of new tokens.
In centralized servers, it's the combo of your credentials to login, along with the servers that update the database.
Once you own a token, you can create signatures for it that other peers can validate. For example
https://firebase.google.com/docs/auth/admin/create-custom-to...
I've already addressed your points about collateral and loans. That's purely business logic, and has nothing at all to do with NFTs (which are _only_ user<>token_id mappings)
So if i have a software licence and i want to exchange it for a concert ticket that a stranger doesn’t need anymore, where precisely do i go, today, to make this happen? What’s the app name or the website i go to? Because i know exactly where to go to exchange NFTs, in a secure, configurable and trustless manner.
> That's purely business logic
Call it whatever you want, the infrastructure that enables it and that is already functional today is only compatible with NFTs.
This doesn't even make sense for most chains since software licenses generally depend on some sort of secrets or drm that can't work on transparent chains (anyone can look at the tx and impersonate the owner to grab an activation code).
The actual product and ecosystem of these things is the hard part. You can't actually do anything at all with NFTs because they are merely mappings of users to random strings.
They have absolutely zero utility in and of themselves. Not as rights to jpgs and certainly not as proof of concert ticket ownership.
The business logic is what makes it all actually work, and can be applied far more easily in centralized systems.
Again, the usefulness in Blockchain is not authorization tokens, it's decentralized consensus, which is only useful insofar as you distrust the centralized alternative.
The auth token itself, whether NFT or any other bearer-like, is neither innovative nor interesting nor inherently useful. It only becomes useful where decentralization is useful and compelling products use it for practical needs.
I'm repeating myself now, no point in beating a dead horse.