That's like 50th percentile for central London for a 2 bed flat.

But central, rather than inner. Of course it's eyewateringly expensive to live in central London. The way London works is that people live in the bits outside the centre, and commute in for work and leisure. People who live in the centre are a bit of an anomaly.

Not expensive at all. Decent standard one beds in an ok area in zone 3 can cost £1500/month easily (about 10km from the centre of London).