So it is not OK for the person in front to put their seat back & cause you discomfort, but it is OK for you to insist that they keep their seat upright & cause them discomfort?
My wife was on a 14 hour SYD - DXB flight a while back & when she went to put her seat back a little in order to try & get some sleep, the 6 foot something guy behind her asked not to recline the seat, as he was finding the leg room a little challenging. She was quite annoyed that he would buy a seat where the leg room was tight for his frame & then cause her discomfort when she was trying to sleep. She had a right to recline her seat & he really had no right to prevent her from doing so. They eventually reached a compromise where she only relined part way. Both ended up uncomfortable for the entire flight.
The point is that it wasn't her problem, it was his. We can both appreciate his difficulty, but frankly, it is up to him to try to get around his height issue as best he can without inconveniencing others.