I think you're right to question it. A single private jet emits up to the emission of 177 cars apparently, accounts for 4% of global aviation emissions, and therefore emitted more than all flights departing Heathrow in 2023. So given that aviation accounts for 2% of global emissions, it doesn't feel like much. But when you account for how few people contribute to this much usage it becomes hugely unethical.

And at least for cars it feels somewhat necessary with the current state of infrastructure around the world (though if they're driving in a well connected city, I think it's equally fair to ask wtf they're doing), whereas very few people actually need to be on a private jet other than the privacy and luxury of it when you have the luxurious enough option of first class.

Oxfam claims that the richest 1% will be responsible for 1.3 million climate related excess deaths so do with that info what you will.