There is surprisingly little genuine film footage of the Titanic both right before and after the disaster, but it does exist.
Sure, cameras in the 1910s were more mobile than those of previous decades, but The Living Image vintage camera museum notes that “cameras of this era still mainly of wooden, folding construction” - heavy and not easily mobile.
Let’s also mention that handheld video cameras weren’t a thing in 1912. You can hear dramatic screaming in the background, but there are no visible people in the frames. How do we know that is is fake? First, listen to the audio.