There are two possibilities:
a) Private Jets are an important source of pollution. Then we should complain about private jets all the time, not just when we want to smear the people who use them to travel to climate talks.
b) Or private Jets are not really that much of an issue on a global scale, and we should focus on whatever is actually discussed at Davos, rather than complain about how people get there.
The article makes no effort to quantify, or put into relation, the actual impact of people travelling with private jets, so I really don't see what it brings to the table, except triggering a bit of outrage here and there.