Roffa,
The use of enhanced mode-s in high density airspace has some clear advantages. However, those benefits have no relationship to equipping aircraft with elementary mode S. I am sure Chevvron recognises the advantages of having altitude preselect downlinked, the ability of your stack vertical view to work and all of the other features which make life in the TMA better. HOWEVER, for us folk who go less than 250 knots, don't have flight management systems, and who don't have altitude preselect and as such down link nothing other than our flight ID - to my knowledge you get zero value from our Mode - S transponders beyond what you already had from mode C - And I suspect this is why Chevvron has made the comment he has.
The logic that because I sometimes go commercial means I should spend money on a nil value upgrade doesn't really grab me. However, at least it is consistent with EASA's view of the world!
And having 10,000+ people each spend £3-4k (something like 40 million quid) for no benefit seems like a poor idea. At a minimum they could give me the money and I would be able to run a couple of Mode-S enhanced Kingairs for a number of years
