Maybe it has been replied elsewhere but I find this attitude rather confronting and unacceptable.
Sure, if you are a tall person... you think you deserve some special considerations flying whY ?
The pax in front, meals finished / trays cleared, has every right to settle down to rest, relax or sleep.
The seat recline function expressly allows him/her that option - notwithstanding your "tallness".
Perhaps, you should employ your "tallness" in some other endeavours to allow you to purchase a Y+, J or F seat which would give you the space you are so specious about.
I find it "weak" to resort to violence - rocking the seat back & forth with your knees - to get your way.
No two ways about it: "guarantee not to get any sleep" is a form of violence !
Uncomfortable, yes... it happens to all of us in Y, even the shorter ones or the lean ones.
Special rights because of your height ?? Please spare us that thought. It is so wrong.
Travel less, save more.... then travel in non-Y class. That would be my advice for any seat rockers !!