My daughter sat in her umbrella stroller right to the plane door as well. She got out, I folded it and set it there, when we got off the plane in Ft Lauderdale (detour to visit inlaws) it was set up and waiting for her to climb in.
I did the same when boarding in Orlando, but upon deplaning at Newark, the stroller was still closed in a pile with other strollers. I guess because there are so many strollers gate checked in Orlando, it would take a while to set them all up.
We had 5 people in our family flying. On our flight down we had 4 carryons, three backpacks and a car seat. On our return flight we had 5 carryons, 4 backpacks and a car seat. Both times I gate checked the stroller (leaving it at the plane door with a tag on it the boarding agent gave me when checking our boarding passes).
HTH!