Selling financial data against a name would be in breach of the data protection act therefore I see no risk, the data would also be accessed by an API therefore anything returned will be a call back and would be in the best interest to cache it rather than store it. the only risk would be based with the consumer and who they pick and the legality of the third party report provider they’re with.
And graphs I wouldn’t call fundamental. Useful, not fundamental, a graph isn’t required for the bank to work correctly, however there are some things that are needed. I agree it would cause less friction and ease of use, but this is for a minority group, but for the users who do not want it, it causes more friction as they’re avoiding the functionality they don’t want. 
I think graphs are a part of a small minority. I can see what Ive spent. I know what I’m likely to spend, I don’t need a graph for it. 
If I want to see my total spend by retailer from highest to lowest, I’ll put it in a spreadsheet and check, it’s not something I need on a day to day basis.
To be fair, with this, when the API is released, I’m looking at building a web app and you’ve pointed out that some want reports and graphs, therefore it’s functionality I ‘could’ build in, which allows users to build their own reports based on what they need in a separate tab. The difference is, I could work on graphs and spending habits, and have my bank secure my money.