I've been genuinely shocked that some people find it hard to believe that you don't have to be posh to go to Oxford or Cambridge. I went to Oxford for my first degree, where I met dh who was doing a masters course. We then both moved to Cambridge when he did his PhD there.
I'm from a low income household in the NE, went to a shockingly bad state comp, and somehow fluked a place at Oxford in the 90s.
Usually people have no idea what university someone went to, but if it ever comes up and we mention we went to Oxbridge, people are a bit 🤔. I even had a colleague at work once, who told me it was my round at the bar because I must be able to afford it if I went to Oxford.