Interesting comment Cabin Crew. Maybe more domestics at Gatwick then. Joking! However it isn't all about the front cabin although that is important.
Also as demand returns and slots become scarcer, (as they will overtime), does a A320 to Mykonos compare to 777 to New York. Some leisure destinations are more premium than others too.
I don't doubt your point but it may depend on destination. BA have also never flown to Mykonos from Gatwick.