They are subjected to the pay scales dictated by bureaucrats and politicians. Of course, they can't attract the caliber of engineers that works for large commercial cloud providers, so they have to settle for programmers that didn't make the cut. And the leadership is non-technical and from the financial and government worlds (you know how these "elites" see programmers and software engineers in the UK...).
The existing bureaucrats running the bank probably see the Cloud as something that will reduce their headcount (why would they have sysadmins and datacenter employees on their payroll when they can simply buy it from a reliable provider), thus making them look less important to other managers. The existing unionized employees see it as a threat to their stable jobs (they are now competing with engineers that are 10x their caliber). That's a pretty bad thing for both.