I’d love this to happen, but there would need to be some infrastructure around it - maybe a not for profit company -rather than purely open data.
I mentioned this before, but a not for profit set up as a contemporary start-up (rather than “traditionally” like pay.uk) would be an even better idea:
I think it would need to wait for this you cease to be a differentiator and something commodotised first though. I wonder how important merchant data is to Monzo as a differentiator…