In the past that's true because why would you want to hijack/blow up your own plane with your business partners / family / friends... but will that remain true if you're booking a private jet with 7 random strangers?
Yes. Because when you have one terrorist plus 10 planes with 100 people each, your chance of getting blown up is 10%. But when you have one terrorist plus 100 planes with 10 people each, your chance of getting blown up is only 1%
