This somewhat assumes blockchain can also deliver on privacy. Perhaps full encryption of the data is enough. But who is paying for all the nodes?
Another way to do this without the blockchain is open standards (think… HTML for example!) and software that lets you export. Where possible run this software open source on the desktop or as an open source web app. Think Photopea as the pinnacle here.
The blockchain or no blockchain approachable both suffer when you have a data format per app locking you into that app anyway.
Re costs: it’s decreasing rapidly. Solana is within 100x of DynamoDB prices so costs are soon becoming negligible. At that point costs can be taken over by the app developer or paid by users on a subscription basis. There are also decentralized consensus mechanisms that don’t rely on paying fees (FBA, delay functions). Idk which will succeed.
Re open standards and “software that lets you export”: we’ve had this for the past 30 years and see how it turned out.
Re lock in: no, in a decentralized database, the data schema is public which means it’s trivial to write an app that works with another app’s data.
Another way to do this without the blockchain is open standards (think… HTML for example!) and software that lets you export. Where possible run this software open source on the desktop or as an open source web app. Think Photopea as the pinnacle here.
The blockchain or no blockchain approachable both suffer when you have a data format per app locking you into that app anyway.