Do Sport England agree the targets with the relevant NGBs, or are they just imposed using some sort of formula at their end?

I'm just curious to know whether the various sports have been set up to fail by being given targets they were never going to achieve.

Personally I think there's an element of that. Not to mention there is an issue with the criteria for compiling the numbers. I coach rugby league every week of the year and play occasionally (7-8 games) throughout the year, yet I wouldn't be included in the RL figures. Neither are, IIRC, under 16's (or it might be u14's, can't remember.)
Yet because I ride a bike alongside my niece (she loves going for a bike ride) I would be included in the cycling figures.
The same as anyone going for a jog regularly would be included in the Athletics figures.

None of that though hides an issue with participation that RL has always struggled with. Hopefully the likes of Touch RL can help with that and be our version of 5-a-side football.

Well, yes, that too!

Also, Andy Gilder's point upthread.

I believe the targets are mutually agreed upon by SE and the individual governing bodies.
Now Nigel and the lads don't have to worry about saving Iconic clubs any more, maybe they could work on a strategy to get more people playing RL?