one cannot in good conscious claim they have "data ownership"

This is a misconception, an assumed evolution of Web3.0 in your argument.

It is true that blockchain aren't that innovative in the Web3.0 sense and platforms like Technorati back in the day were the real innovators (also microformats and schema.org by Google).

But at the same time blockchain are the platforms trying to bring the semantic functionality to the user. Because that semantic functionality is key for Web3.0.

And that is perfectly visible in concepts like MAKER DeFi or even here on Hive. The data can be accessed and used by different bapps (Blockchain apps, most are centralized rather than decentralized).

As such the argument about Web3.0 should be built around data portability rather than ownership. And there decentralized blockchain do play a rather nice role and as we will see always more interaction between chains they will become a true multitude of Web3.0 nodes.

Blockchain are the "Fat Protocols" (see placeholder.vc) which are the nodes in Web3.0.bapps are users.

I totally agree with your point of lack of data ownership btw. A lot of bapps also run Google Analytics and many other centralized scripts which... is kinda ironic and also sad at the same time.

Lastly, while the outcome was exactly what you sketched, Web2.0 was defined by User Generated Content (UGC), not by offering the account layer as such. Self-hosted blogs are also Web2.0. But I realize that's semantic pettiness since the outcome was exactly what you described. I was always a a of openID, the first large scale effort for "account portability" but once the Goliaths understood they could centralize said portability by using their own vast database of accounts and making it faux-portable it was game over for openID.