I had to look that one up tbh, yes I bet those brakes clog up quite easily on muddy cx races. Most on discs these days I guess?
I have never owned a CX bike and have spent the last 32 years avoiding racing cross so unlikely to start now
It's not that they clog, but when you are constantly running rim deep in wet mud, they become pretty ineffective. Disks, being out of the way, don't suffer from that. So, yea, mostly disks these days - if I jump off my Charge Plug 5 onto the Simba I go from 'will my grip hold?' to 'Erm, where did my brakes go?'