Comment by viraptor
The format exists - OFX https://en.wikipedia.org/wiki/Open_Financial_Exchange
But even banks that use it make massive mistakes and break the basic assumptions. Unique ID repeating in the same day for example. Or using the minutes in place of the month...
Banks are much less technological than the common stereotype about them. In fact, integrating or automating a bank is one of the worst things you can do. The list of easy integration goes like this: