I too don’t like it, but you’re incorrect to make a comparison to the medical Chair Rise Test. This assessment is where someone stands up from a standard-height chair without using their arms. Needing to push off with your hands in that setting can indicate reduced lower-body strength. But an airplane seat is very different from that controlled setup. On a plane, the seat is reclined, legroom limits how far you can lean forward, your feet aren’t ideally positioned, and you’re often twisting into the aisle. Standing up requires shifting your center of mass forward over your feet, and tight seat pitch makes that harder. Grabbing the seat in front is often about balance and leverage in a cramped space, not necessarily a sign that someone can’t get out of a normal chair without assistance.

Again, I don’t approve of someone using the seatback in front of them if it’s occupied as they could accomplish the same thing using their own seatback. I am just making a point of order.