I know exactly how PCP works, tyvm.
Given that the usual deposit required to order a car is £1k these days (used to be less!), that's how much I've put in as my deposit on the last couple of deals. I then pay £x/month until I get rid of the car. That works for me, and total amount paid is roughly equivalent to or less than leasing examples I've looked at for the same car / colour / spec (yes, you can get some very good lease deals if you're willing to be flexible on make / model / colour / spec, but that's the same with buying). It might have helped that I've always got a good deal that includes a low interest rate, making switching away from the PCP a bit pointless.
Out of the 2 PCP deals I've completed with VWFS so far, I've handed the car back once (Octavia vRS) because it was worth less than the MGFV and the dealer through which I ordered my first Kodiaq didn't want to do trade-in (fair enough, really), and the second deal (my first Kodiaq) ended with a huge lump of equity thanks to the anomaly of used car prices rocketing skywards through the second half of 2021. So yes, the equity being greater than expected was a good thing - but it had absolutely nothing to do with the PCP deal. I even said in the post you quoted that it was down to good timing rather than anything else.
PCP deals were originally designed so you would end up with equity - but because people concentrate on the headline £x/month figure, they soon changed so that the MGFV is as high as can possibly be so the £x/month is lower. I'd argue that this is a gamble on the part of the finance company, as if the car is worth less at the end, they're the ones that lose out, not the customer (well, assuming the customer hands the car back and doesn't trade it in with negative equity... but I guess some people probably end up doing that out of ignorance of the way it works). Also, I'd argue that PCP does benefit the customer - or, at least, a certain profile of customer. If you're wanting to buy a car outright and keep it for many years, then a PCP probably isn't the cheapest way of doing it (certainly not as interest rates get higher and higher) as you're probably paying more interest on the balloon amount than you would otherwise. However, if like me you enjoy (and are able to) a change of car every few years, then it's a simple way of doing that without having to worry about what the car is going to be worth - again, you have to understand how PCP works and use the correct option at the end of the deal, otherwise you can lose out big time. I'd argue that I've benefitted in different ways from the two deals I mention above, VWFS took the hit on the first car and I took the rewards on the second.
This. I'd lease a car if I found exactly what I wanted for less money, but I never have. I don't intend on hanging onto cars for more than a few years, so PCP is just renting to me. If I end up with equity by any miracle (or anomaly!) then it's just a bonus that makes the payments on the next one a little bit less.