But most UK road races don’t have twisty, technical descents unless you ride the big E/1/2 races.
True, but I can think of a race last year with a fast decent followed by a sharp left turn where braking was definitely needed. I can’t see how someone with greater braking power (i.e. discs) would be a danger to anyone else.
There’s never a situation when you need to stop in a race unless there’s already been a crash ahead, and even with only rim brakes in the peloton some stop quicker than others – mainly due to reaction time I would say.
I think it’s inevitable as discs are clearly superior, so I’m happy it’s been bought in now. To say all discs or none would make it very expensive for a lot of people to race next year. They’ll be a time in a few years when nearly everyone will have discs, so the sooner this process starts, the better IMO.