@goodbyestranger
getintoteaching.education.gov.uk/train-to-be-a-teacher
The current means of getting into teaching is quite regulated and QTS is fairly mandatory. The school where QTS training is offered in my experience is fairly prescriptive though available to anyone who fulfils a certain standard (degree and a minimum of 4 in GCSE maths and English).
Demand for teachers has always in my experience been high and successive recruitment drives have tried to bring in teachers from a range of backgrounds. I know a fair few teachers without Oxbridge degrees for example.
Senior Leadership teams in my experience tend to look at performance during the AGE stage primarily as the training assessment acts as an indicator of the quality of teacher (hence me saying university attended may not be a paramount factor for successful applications)
it is a rally good thing Oxford and Cambridge graduates are moving into teaching and obviously I am sure they will be passionate about their subject.However I certainly know that a lack of an Oxbridge degree won't be a barrier to progression. There is no specific targeting of Oxbridge grads for teaching as there may be for say investment banking and the marketing of teaching as a profession is fairly distributed amongst the majority of universties..
I would think that graduates from any university wouldn't limit the type of school they teach in and as has been pointed out the majority of schooling in the UK is comprehensive.
the overall point is that if your ambition is to become a teacher then you have realistic chance of getting a job from a wide range of universities therefore Oxford and Cambridge do not necessarily offer a significant advantage. Remuneration for teachers is on set scales and therefore university has no bearing on this (at least in the public sector).
It sounded from your post that Oxford and Cambridge educated teachers are only to be found in a certain sunset of selective education but is this the xase?
I agree that satisfying careers are sometimes not well remunerated and happiness i n life is I guess paramount. I guess a lot of this comes down to how you define a 'great career'. Good education and projects are not a monopoly of two universities.