That is profoundly untrue in my experience (13 years of working as a Dev manager at UBS and BofAML). The knowledge of how the business really works sits largely

That is profoundly untrue in my experience (13 years of working as a Dev manager at UBS and BofAML). The knowledge of how the business really works sits largely with the long-served IT and Operations staff. This is certainly the case in the back office (clearing and settlement) and in the regulatory space. I can't speak so much for the front office, but it seemed that the developers with successful careers were those who understood the business and therefore could talk to traders and desk heads in their own language (far more successful than the developers who were actually any good at producing maintainable software, but that's a different rant). There are lots of things wrong with technology in large banks but the business knowledge of developers is pretty low on the list. I left banking a few months ago, so I am no apologist for the sector.