Ignoring was the best thing to do but if you are going to respond, this is essentially a perfect response.
Zack has crossed the line into genuinely creepy stalking, timing how long drinker and his friends talk about certain shows on live-stream, making increasingly bizarre demands in regards to what opinion drinker is allowed to have on random pieces of media, making creepy call-out posts every time drinker coughs, burps, or eats a sandwich.
I don't see how Zack doesn't realize how weird and obsessive he is being, like you could make a case for the idea that youtubers who build their audience by making snarky roasts of movies are incentivized to lean negative, or maybe do feel a kind of pressure from their audience to say they didn't like something even if they liked it. How their audience will react probably does play some role in how they present their opinions, so there is a kernel of something in what Zack was maybe trying to say at first but he sperged out too much and has now turned it into this vindictive obsession and nearly everything he says is fucking nuts.
In short, dudes a wacko.