I am an American traveler and I might be overreacting, but there is one behavior on Air India flights that I have found very hard to ignore.
During flights, some passengers tend to use the headrest of the seat in front of them for support when walking back to their seat or adjusting themselves after using the restroom. They will literally grab the top of your seat while you are sitting in it, which ends up shaking or jolting your head and upper body.
I have even been woken up twice on long haul flights because of this. I have not really experienced this level of physical contact with seatbacks on flights in the US, so it feels quite jarring to me.
I find it very uncomfortable and honestly quite frustrating.