This depends on the person in the wheelchair. If the man was alone, it is likely he has enough ability to stand or scoot. I am in a wheelchair. But, my arms are stronger than average. The bars provide support for pulling up to a standing position. If a person was not able to stand, they would scoot over to the toilet.
I have been in a weaker state in my life. I would scoot to a sideways position. Once I transferred to the toilet, I would turn myself around. An electric wheelchair will not move when it is turned off, so it provides a stable support for transferring. A manual (non-powered wheelchair) has brakes that will lock the chair in place.
Believe it or not, being in a wheelchair is thought to be the major hindrance by walking people. In truth, transferring can be the toughest task. Human resilience is a mighty thing. You learn to adapt to any situation when you face a new challenge. Otherwise you die. I have a quote that I always keep in my mind. A philosophy if you will.
“Empty your mind. Be formless, shapeless, like water. You put water in a cup, it becomes the cup. You put water into bottle, it becomes the bottle. Put it in a teapot, it becomes the teapot. Water can flow or it can crash.
Be Water my friend”