I suppose we (not just CIHY) need to define takeoff and where this ends!

5 seconds after the wheels no longer touch the runway? I'd say the plane is still taking off. In fact at that angle of ascent it would be nearly impossible to not recline a seat without it jolting back.

In a perfect world people would still be able to recline their seats (without them pressing on the knees behind although that could just be me), they would do it at a time when the seat won't cause bruises (in my book at or very near level flight) would also do the civil thing of 'do you mind if I put my seat back please please - sure, no problem'.

Thing is we're all different and where one rule ends we will all be different distances away from it.

40" pitch seats in Economy? Sorry, dreaming again.