Before takeoffs and landings, FAs always announce that "seats must be in their fully upright and locked position". IME this is usually enforced during the final cabin check. In fact, I've always assumed that the "seats fully upright and locked" rule is a safety regulation that is required by the FAA.

However, on a recent domestic DL flight on a 757 with the regular recliner seats (not shell seats and not the international flat beds), the aisle seat of the guy in front of me was partially reclined as we left the gate and taxied toward the runway. The recline was clearly and obviously visible, especially since his seat mate's seat was not reclined, so that one could immediately see that they looked distinctly different. [The stranger seated next to me at the window appeared to be at least overweight and to have somewhat of a mobility problem, but didn't pre board FWIW.]

When the FA passed my row during what appeared to be the final cabin check, I pointed out that the seat in front of me seemed to still be reclined. The response I received was a shrug, followed by the comment that "Oh, it's OK. The seat is only slightly reclined." By now the lead FA was at my seat too and she didn't correct her colleague or do anything either. I commented "Well, I care about my own safety in an emergency" but was afraid to push the issue further. [I didn't want to cause a return to the gate to be kicked off the last flight of the day or ordered to move to a middle seat in coach.]

These two FAs (lead and the other one who appeared to be very experienced too) knowingly allowed the same situation for landing: the seat of the guy in front of me was again very obviously not fully upright and neither FA asked the guy to put his seat up, nor did they try to do anything to adjust the seat. In both cases, the passenger was awake so that asking him to put the seat up would not have disturbed a nap.

[During the flight, the guy reclined further, so the seat didn't appear to be stuck in the partially reclined position. In addition, he and his two kids appeared to be traveling on paid FC tickets. There were no signs that this was a broken seat given to a nonrev, not that seats with safety rather than comfort issues should be assigned to nonrevs.]

So what's the collective wisdom here? Is my understanding correct that the seat absolutely should have been completely upright for the actual takeoff and landing so that my seatmate and I could deplane more quickly if there had been an emergency situation? Is is this a requirement that permits a lot of wiggle room?

Thanks.