It's like saying that the 3 Ferraris in the city are the problem, not the million Volkswagens (or whatever).
Heck, if this helps those folks focus on the problem at hand, I'd rather have them fly private than go through the stress of flying regular (which in my view is mostly horrible).
But the inequalities were already there. It's not like if they stop flying private, they'll all of a sudden be less wealthy. At least they spend their money, instead of hoarding blindly (not that flying private changes this by much, I have to admit).
Someone indirectly advocating for such things while flying in a private jet is a pretty bad look. It reminds me of a medieval king gorging himself on food while telling the population to slim down.
It’s really easy to claim “every one should do X” but then exempt yourself from it. It just looks hypocritical.