Meanwhile, I have a story in which I offered to switch and the offer was ignored.
I was flying PDX-MFR in a Jetstream 31, in which seating was 1-2. I was assigned to a seat in the 2-side side, with an empty seat beside me.
The row in front was the exit row. The two seats in that row were taken by a woman and a boy, possibly her son, who appeared to be about eight years old. The crew (co-pilot, iirc, as there was no FA) asked them to move, because the boy was too young for an exit row. They refused, then switched seats with each other - which made no difference. A complicated seat-swap discussion ensued with the passengers on the 1-seat side, to no avail. I offered several times, loudly I thought, to switch with them, but neither the woman passenger nor the crew member paid any attention. The boy was finally moved to the only other empty seat, but moved back as soon as the co-pilot wasn't looking.