Requests to change seats should be made to the flight attendant, not to the passenger. Ideally, the passenger with a pressing, real need (not just a want) for a seat change thinks ahead and discusses his problem with the agents at the desk in the boarding area, who can alert the cabin crew. This is what the family of the elderly lady (see below) probably did. In literally hundreds of flights, I have been asked only twice to change seats, once by the flight attendant to allow a very elderly and frail woman to sit next to a member of her family, who was seated next to me. Of course, I agreed. The
The other time, a woman in her twenties, some 30 years younger than I, travelling alone, asked me to change my aisle seat for her center seat, and "because it will be easier for me to work on my computer." That one I saidturned down with "Do I look stupid? Certainly not!" OK, this wasn't tactful, but this was a time not to be tactful.
If the request does not come from a flight attendant, just say
Talk to the flight attendant if you don't like your seat.
If the request comes from a flight attendant, consider the reasons and either say yes, of course (as I did for the old, frail lady) or no, sorry, I'd much rather not. Do not engage with a pushy passenger.
Some readers will correctly object that flight attendants are too harried on today's crowded flights to do much seat-rearranging. Precisely! But they will make time to deal with an urgent request involving the very old, the disabled, and young children. All others should just settle in and endure.