Finished it. Here's a summarization attempt, TL;DW:
1. The concepts of pro and anti encompass a wide variety of different things and also Twitter is a hellscape so people Ship of Theseus everything, taking fairly innocuous comments and extrapolating a whole nonsensical narrative out of them. Many people on either side of The Discourse actually agree on some things, but because of semantics they label themselves differently and throw dogshit at each other.
2. Both sides engage in harassment campaigns.
3. Many of the things pinned on antis (such as various suicides and the needle cookie incident) either had nothing to do with shipping wars and were retrofitted to the discourse, or were completely faked. People act all sanctimonious because they think there's an actual body count when there really isn't, and if there is it's a lot lower than they think.
4. Antis watch too many kids shows, proshippers treat any and all criticism of the things they like as death threats or whatever.
5. Go outside
On a related note, Sarah Z deactivated her Twitter before uploading the video, which is probably the most sensible thing to do. She ended up on the trending tab for a bit, and just like what happens with literally any video that's over 15 minutes long, there were people on Twitter getting mad over things that she never even said, which is pretty funny.