Challenge: write as concisely as possible but with all requisite statistics, an argument aimed towards the red-pilled as to why the momentum in the demographic shift in the UK is too great to overcome and why there is basically no hope.
It's hard to be concise when you've got to demonstrate it's happening, demonstrate behavioural differences between the races/ethnicities, demonstrate that they're deeper than just cultural/economic/social differences, then explain the ways it could be curtailed before demonstrating why they're all non-starters.