What's the Point of the Central Scorecard Challenge?

How much sway does a host's country have on the ultimate outcome? Is it more about making sure which things are at the centre of the conversation? The french presidency did a really, really good planning job. But i think they woke up far too slowly to the central score card challenge. Maybe if johnson had built alliances, rather than doing the opposite,. he could have unlocked this high ambition coalition early and put pressure on countries like china.