I watch him every day. He keeps the same “handkerchief” next to him during the show and uses it many, many times during the broadcast. He doesn’t really blow his nose into it, but merely dabs at it. Might be for allergies or something. He has apologized for this action in the past. He does not cut the video feed when he does it.
Some Chemo causes your hair to fall out. A lot of folks don’t realize that means the hairs in your nose as well.
My sister had a runny nose for a year. But my wife never lost all of her hair. It got thin, but never went “bald.” She had me shave it for nothing. Came back thick and curly.