I think this is the big sticking point the author is getting stuck on. If the movie is great, who gives a shit what they did to get there? If some want to champion the work they did, let them. But if you did all this work, and all you have to show for it is something that looked like you trotted out the camera for a day or two every year, then yeah, you shouldn't be immune to criticism.
That's pretty much what he's saying. All he's saying is "Regardless of the quality of your film, how difficult it was to shoot is not a contributing factor." Which is absolutely correct and I don't know why anyone would disagree with that here, regardless of whether you enjoyed The Revenant or not. He obviously didn't (or at least, wasn't blown away by Leo here) and he's expressing his disdain with an industry too focused on the difficulty of something, rather than the end result, which is really all that matters.
Like, this:
Leo was great in The Revenant, as he is in almost all his movies.
isn't actually super relevant to the article. Like it's related, but it's not the crux. Surely, regardless of whether you thought Leo was good here, and regardless of whether the shit he put himself through to output that performance, you still recognise that eating a bison liver, or living through horrible weather conditions is not in and of itself good acting and shouldn't be used to drum up credibility to a performance.
And this:
Just watched this today. I really enjoyed it. Some people can never just enjoy things.
Why is this guy trying to make me feel bad about enjoying the film?
Regardless of the relatively antagonistic attitude written in the article towards the movie, you or me or him enjoying it isn't super important to the discussion. Stop looking at these things as "I enjoyed x and it's 100% subjective so get off my back wouldya" when the crux of the argument isn't about the film's quality at all. He's talking about a larger issue he finds problematic when critiquing art. And he's totally right.