Here's a more complete picture. Sweden is consistently among the least affordable across metrics: https://www.oecd.org/els/family/HC1-2-Housing-costs-over-inc...

> The median burden of rent payments for tenant households is highest in Finland, the Netherlands and Sweden (30%), Norway (29%), and Denmark and the United Kingdom (28%)

That said, it's not very different from its peers, so I doubt rent control is having a huge effect.