One thing to add that I just found and looked into is that Peertube does seem to have a way to sort by license, atleast on sepia search, which is like a global search for most Peertube instance, though probally not every video gets featured on all instances ever made. So that seems to suggest even more that is is case by case basis whether it is legal to just go and download the videos freely.

My other concern is that not every video upload has a license submitted, those videos uploaded to a Peertube instance, that say that the license is 'unknown' it's due to the uploader not deciding and that just complicates things further for whether it's okay or not okay to download the video.

If we are going for this fediverse and opensource thing especially with video, legal use like this need to be looked into, simplified and more talked about so people can rest assured they are in the right legally. Even if the uploader might not be as likely do anything, it's still an unknown license and that could leave people vulnerable especally in more creative cases especially when they reupload with little fair use to there aid.