I doubled my salary by leaving the Civil Service.
I don't claim to have been a lynchpin or a massive talent, but I was one of a number of people who couldn't afford to stay.
Technical ability & strategic thinking is undervalued compared to managerial & budgetary skills.
And the pay erosion meant a lot of the best civil servants - particularly after 2016 when relative pay had really fallen and things got a bit chaotic - just decided enough was enough and hopped off to the private sector.