I have found that those girls (I work with girls) who were ambivalent about Oxbridge were more enthusiastic about going after visiting for their interviews.
One of the huge advantages - psychologically - of this year's online process has been a certain detachment, compared with going to 'live the life' for a couple of days then more than likely have that possibility taken away.
DD was lucky enough to visit the university in person, but not having the interview complicated by staying in college, meeting potential friends and tutors etc has, I think, lessened her emotional involvement with the process.