Sorry I can't help with your question, but I wanted to ask what features you feel Jellyfin is missing that is keeping you on Plex? I've made the switch, and actually like Jellyfin better.
Just went through this myself and settled on DIY build. Someone recommended this video, and I followed it very closely. The built was so easy and less expensive than off the shelf. I installed TrueNAS on it and couldn't be happier.
That is a good point, but if it's not Firefox like my pixel is telling me, then what else could it be on a brand new phone? (I know you can't answer this)
I believe your characterization of the developers is unfair. This appears to be an isolated incident by a single developer, and to take that and paint a picture of the entire team as dickholes isn't right. I'm not even sure judging this individual by his worst day is fair, but that is up to you.
Sorry I can't help with your question, but I wanted to ask what features you feel Jellyfin is missing that is keeping you on Plex? I've made the switch, and actually like Jellyfin better.