Are videos made before 1923 in the public domain? For example this made in [edit 1897] by Edison. Hypothetically, could I edit this video for commercial purposes and use it in any way I wanted to (excluding defamation)?
Yes, any film made prior to 1923 is in the public domain - under US copyright law. I can't tell just by looking when that youtube video was made, but it appears to be prior to 1923.