Well, personal opinion: I don't think it's clear that the UK Civil Service has been more of a blocker to Brexit than they would've been for any other earth-shat

Well, personal opinion: I don't think it's clear that the UK Civil Service has been more of a blocker to Brexit than they would've been for any other earth-shattering policy change. Part of the social contract of joining that sector is, I expect, that staff will be working across successive governments and policy changes, and yes, people are going to have some personal connections to day-to-day events, but the professionalism and processes of the institutions involved are intended to minimize and overcome those biases (and apply correction when they aren't, with supporting evidence and investigation). That said, identification of weaknesses and opportunities for structural improvements are welcome. "Wait a hundred years" is always an option, although if there are shorter-term risks then I'll always be listening for those.