The post you've quoted says they "could suffer more severe consequences". On the virus transmission side, that's just based on the sharper increase in cases and the higher number of daily cases, especially after doing so well to keep cases so low, and the development of specific hotspots which posed the biggest problem there last time. Which I'm taking from local's comments in here plus the supporting data. On the economic side, that's largely a byproduct of it: a more strict response leading to more economic damage.
But that's not really the point I'm making, so if it's a point of contention, I'm happy to retract the statement. The broader point is that if the measures were much more appropriate, and much better adhered to, then you would have expected the UK to do significantly worse - especially at this stage. And there were a lot of people in here saying that is why the UK was going the way it was, while Italy was keeping things low. Is it an unreasonable point to question how influential those measures can be when the conditions worsen, or alternatively how well they were adhered to in their respective countries?