> no bank provides free APIs to access this for consumers, the only option is to download manually/scrape through their websites.
In Europe they will have to provide the API thanks to PSD2: https://softjourn.com/blog/open-banking-api/
> Ad tracking/browsing data is another. The current model is the people making the trackers own all your data. A model where WE own our web activity data and selectively choose what to expose to websites/advertisers would be much better for consumers.
I don't know how this relates to blockchain at all. Blockchain by design is public and replicated to anyone. How would you withdraw your data from there?
It's not public, it's just massively replicated. Your data on the blockchain is encrypted. Only you with your private keys can decrypt it and decide with whom to share it with.
Credit agencies like Equifax also own our credit history data, and generously sell it back to us - 1 free report a year, rest you pay for. While also selling it to other companies without our permission. Which employers can get their hands on via background checks, again without our consent. Not to mention one of them recently got hacked and leaked everyone's SSNs. Their entire model is capturing our data and selling it to others. We should own this data, and choose if and when we would like to provide it to a bank to get a loan etc.
Ad tracking/browsing data is another. The current model is the people making the trackers own all your data. A model where WE own our web activity data and selectively choose what to expose to websites/advertisers would be much better for consumers.