Your post is very detailed and interesting, but the comparison has a slight flaw in that VS's (new) Upper Class is sold/advertised as a first class product and therefore you should have compared it to BA's FIRST. Looking at your 'summary of differences', many are provided at BA, but exclusively for FIRST paxs.
The recurring issue with many of BA's CW passengers is that they find it difficult to accept that they not a first class pax and therefore are NOT entitled to certain 'luxuries'. A first class pax is easily discernible from a business class passenger in that the latter can be overly demanding while the former takes luxury in their stride and will generally demand nothing!
I suppose at the end of the day, it does boil down to prestige and those that can genuinely afford to pay full fare first class will probably do so with BA because of the exclusivity it offers while VS can offer a pseudo-first class to cater for the wannabe first class business traveller......I think they call it clever marketing........