Just because rent control negatively affects supply doesn't mean bad supply is only caused by rent control.
I live in London too and I'm baffled by the lack of tall buildings in pretty central parts of the city. The real solution is more supply.
> Rent control is a band aid while that happens to keep long term (especially elderly/vulnerable) renters housed.
At the expense of people who don't currently live in London but could, such as immigrants or people from poorer parts of the country finding a good paying job here.