In my case, on the last flight I was on, when sitting bolt upgright and with my butt as far back in my seat as possible, there was maybe an inch between my knees and the seat in front of me. The tray table didn't come all the way down either.

Its not a case of thinking I have some sort of privilege that would be infringed by the person in front of me reclining their seat - it simply didn't work. the seat in front of me reclined ~ 1/3rd of its normal distance before hitting my knees, and there was no way to get my knees out of the way. In that case I apologise to the elderly gentleman in the seat in-front, and after he glanced at my knees he (very considerately) concurred that getting the full recline out of his seat was 'unlikely to work'.

Sometimes I try to pay extra and reserve an exit row seat, sometimes they aren't available. The last time I got one I ended up wedged between a rugby player and an obese person for ~12 hours, It's not always an improvement, nor is it necessarily cheap.

And like the poster somewhere up-thread, I don't like being a hypocrite, I try to recline my own seat as little as possible.