You might be onto something. I think it's to do with the fact that self hosting attracts a certain crowd, and when you have a product that is popular to self host, but is not open source and with some paywalled features, it irritates them deeply. The narrative is popular enough to hate Plex that I suspect some people who don't even care try to farm karma from the bandwagon. Podcasts like selfhosted.show also ride these tropes...