London faces a housing crisis, yet apartments aren't selling

It is ironic to see protests about a housing crisis in London when the prices of detached houses and villas are skyrocketing, while apartment prices are crashing and listings are barely selling. It really shows the anti-apartment sentiment among Europeans...
However, from what I've heard, British apartments aren't like the Korean style; it seems more like a land-lease model where you own the building but pay ground rent.