At the risk of sounding like a scratched record, it is for clever people who are passionate about their subject.
This chimes with what was said in an online session provided by Cambridge NatSci Biology this summer. The chap who interviews for Pembroke said 'we want your PS to be full of how your interest developed, which strands you've followed & how and what currently excites you. We have zero interest in DofE.'.
@icanbewhatiwant The 'how' could be books, TV, MOOC, podcasts etc. They recognise real-life experience opportunities minimal due to covid & cost so not available to all.
It was a good session but DS was put off by the amount of maths. They mentioned maths a lot.