I do like to use VS when I can, but they are one of the few airlines that still have the "fluff" from yesteryear. Unfortunately the likes of easyJet, Ryanair, Wizz, Jet2 et al have watered down the product so much, Virgin's cost base is indeed just too high these days.
If you have flown VS for any number of years (my first flight with them was 25 years ago), you will know that a lot of the "fluff" has either gone or been reduced over the years.
They are a long-haul only, full service airline, with an all widebody fleet. Completely different operating models and markets to the short-haul low cost carriers you quote.
If you're going to make comparisons at least make them meaningful!