Not querying the value of an EPQ at all, but to add to the debate, what is the potential value of doing an EPQ to a student, as key.
If it is to try and secure lower offers, or develop skills they may not have had a chance to nurture within their standard A/IB courses, give them a talking point at interview etc, then all great.
DD didn't do one (did an extended Research Project marked internally only) but opted for an AS instead in Maths. High risk as not her strength subject in spite of 10 x GCSE 9s, lower points for UCAS (not relevant to her), CAO (Irish, is relevant to her) and is subsequently borderline B/A predicted against 3 predicted A* A levels.
But, she felt that whilst a nice to have, she didn't need the fall-back of lower offers, but did need the scheduling slot to develop extra maths skills, which may come in useful for her post graduate options, especially where there may be psychometric/assessment centre requirements. This was of higher value to her, and personal to her needs.
It may all well back-fire as she's awaiting offers now, but if your application really doesn't need to demonstrate EPQ credentials, then it does place a lot of students under unnecessary herd pressure. I think it's great that so many posters' DC have benefitted from submitting one and got a lot out of it, but those contemplating it should query the 'why', beyond well everyone's doing it so I have to too.