He is the Pied Piper of the miserable branch of the community. He gets (seemingly) very angry about the dumbest, most inconsequential things. I watched a little bit of one of his Tarkov mod videos and he got so upset about the vanilla gun animations (reloading, etc) because of how much he liked the mod's animations. Like, who cares? In the immortal words of the legendary film director, William Friedkin, "I don't give a flying f@#k into a rolling donut" about the damn reload animations. The vanilla reload animations look like reload animations to me! No one is hanging reload animations in the Louvre next to the Mona Lisa. Who cares if they have a few more frames or not?
A few things to consider - it could be his age. When I was a teenager, thinking everything sucks gave me a false sense of authenticity. Or, he's just not a happy person. Or he's out to get TFP because they personally hurt his feelings. Or, negativity sells. Youtube is rife with negativity. Videos with titles like "The Downfall of...", etc, etc gets the clicks, which is my biggest gripe with YouTube creators, generally. OR...it's a combination of all of it.
Over the past few years I've made it a practice to not engage with things that @%$# me off too much...unless it pays me money...and it would have to be way more money than he'd be making off YouTube. If the game makes him that upset and no one wants to watch him play anything else, if I was him, I'd quit YouTube and get a regular job. He's stuck. He's stuck having to act miserable and he's stuck playing 7 Days to Die, because viewers don't like change.