[hnaccount_rng]

You are missing two parts: 1) _during_ the whole “transition” period nobody knew anything how this would pan out. That means nobody* would write grant proposals for ERC funding for the future. Which is the drop in received funding that the UK institutions start seeing now 2) highly trained people do have a choice in moving. And the UK very openly communicating: we don’t want those stupid foreigners made a number of people thinking twice of going there. They are still some of the most famous universities which reduces this effect, but still it was the default choice for anyone and isn’t anymore.

So you get an atrophied bureaucracy for distributing research money and combine it with a reduction in applicants and you get fewer graduate students about 2-5 years after you switch.

*significantly fewer people