Why wasn’t he drugged and gagged ?
Because of a suicidal belief in "human rights" that has pervaded Europe for some time now thanks to the idiotic EU "human rights" convention that puts the interests of foreign criminals before the rights and interests of indigenous citizens. That's why.
The same sort of idiotic dogma that allows MS13 gangs et al. to thrive and prosper in the US.
They should have restrained him.
Anyone who acts up on a plan should be put in restraints.
If you want to have a hissy fit, do it on the ground outside the plane.