There’s a sandbag in front of the lectern, and it does look like that’s what he tripped over. Lack of awareness of his surroundings which isn’t surprising for someone with dementia.
No one else tripped over the sand bag. It was just our joke of a fraudulent leader. If they keep pushing him out there to pretend that he is cognitive and competent they are going to get him hurt, his puppet masters are committing elder abuse.