BA seat is a totally different product as seats go by pair. I find it far better than the new CX seat, and wonderful for couples travelling together as you even face each other. But there is a big difference if you can get the upper deck (F class feel) or are stuck in the crowded main deck.
Regarding VS, I believe that they transformed the 747 middle seat after they were already installed (at least on some planes). I might be wrong, but I do not think that it would be a major transformation to designate some adjacent seats for couple (say 6 of them) and change the partition for those. But that wont be a great couple seat anyway given the fishbone design where one pax will sit kind-of-infront of the other. On VS 747, there are six true pair-seats (middle seats).