Genius ? No. You have to be very competent. Look @ some of the profiles of the people who are quants where you want to work. It’s rare that they are widely cited or well known - they usually are just PhD grads in STEM from top programs (Unless it’s Renaissance) . If you only have a BS you need to be exceptional, if you worked @ FANG & shipped something important or worked for a big research lab (Los Alamos, CERN) you could get an interview for sure. Point is you need a hook. Just going to Oxbridge isn’t enough you need something to point to of how you are way above average. Hope that helps.

P.S. the geniuses are still in academia

Yes yes yes yes that’s where we take our Mensa tests and eat out FOOOKING BISCUITS NOM NOM NOM * eating with Genius noises *