If we legally mandate this what will the consequence be for small businesses that can't afford the cost to comply? (Even if you mandate it for only the big players - what if there end up being only three players who can afford it, they do it well, no one else does and you end up with only three banks?)

I'm super supportive of banks opening up their data for the reasons in my prior post. But the second order effects of regulation are often overlooked--this is exactly what has gone wrong in the US financial industry where we used to have thousands of credit unions across the country and since 2008 most of them have been driven out of business by compliance costs. Naturally the handful of banks that remain are the ones that were the biggest and had the best lobbying effort in Washington...