As to your argument; the re-uploaders create additional value of their own, and it's no less derivative or valid than the work of a streamer.

Derivative work is well, derivative, and it's regulated by the law, whether it's a translation or sampling of music or video compilation. Depending on the country/state the definition by law differs, but generally you're allowed to use only small portions of other people's work and there's a requirement to create something that is significantly different to the work used, so that it can be considered as an original piece. So re-uploading is very fringe activity in the eyes of the copyright law.

Re-uploaders pare down lengthy streams, edit multiple streams together, and engage in other content modifying behaviour. Their work, though derivative, should be tolerated if we're going to tolerate the behaviour of streamers. Streamers argued for this tolerance, after all.