I always dislike this line of argument, it feels unproductive.
I detest frivolous use of fossil-fuel private jets and all flights of them should absolutely be taxed to the roof and the funds used for climate mitigation.
However, if you’re a bigshot person who can have outsized influence (like POTUS or some billionaire or something) then by all means attend the relevant conferences and make an impact.
If your beef is that the conferences are not effective then that’s something we can discuss, but don’t distract by talking about the way people arrive, unless it’s to propose some kind of carbon/pollution tax in which case I wholeheartedly agree.