I was going to reply to grandparent that only flat prices are coming down because of rising service charge costs, and being hard to mortgage because of cladding issues.

But after some research it is indeed true that house prices are, to a lesser extent, also going down, at least in real terms, if not nominal.

I actually wrote a webapp to show this, check it out - https://housepricedashboard.co.uk/

London house prices are falling quite a lot in real terms.