This is only true of the data stored on the blockchain itself. As described in the article, that isn’t anywhere near enough to replace the centralized systems being billed as “web3”, and it’s completely unworkable for data which can’t be public, which is updated frequently, or which needs to be deleted. Combined with blockchains being unavoidably quite expensive and slow, and the challenges of standardizing protocols while the competition is shipping it seems quite unlikely that this will change.
It doesn’t reduce lock-in meaningfully if Google were to continue to store and process all of your data but now you’re using an outside authentication system. I’m sure they would love, however, the way “web3” makes their job of tracking users so much easier.
For data that needs to be updated, all you need is an override mechanism, which sounds simple enough.
For updates, you can definitely replace things but that's expensive if you have to pay a transaction fee regularly and it could quickly get to non-trivial storage sizes if you have to store obsolete versions in perpetuity, especially with non-trivial metadata overhead.
As we have clearly seen with OpenSea and rampant fakes, copies, plagiarism etc. Oh wait...
We already see this with blockchain payments. The vast majority of merchants who accept cryptocurrency payment do so through a service that manages their wallet and typically offers some kind of value-added features to lock them in. There is no reason to believe the same will not happen with Web3, if it is not happening already.