The upside of the Open Banking regulations which have swept jurisdictions like the UK and the EU is that many more challenger banks have appeared. The headache for either incumbent banks or for upstart startups is the very proliferation of these new banks and financial tech products. But as we know, in gold rushes, the people selling the picks and shovels usually win. Thus, startups have turned their attention, not to launching full-stack banks, but to full-stack platforms that other people can launch their fintech startups and products upon. The…