As someone who does, his videos tend to always have a critical flaw in the premise which makes his main point simply not right.
I only remember 4 videos of his I've watched, the one on Fallout 3, Bloodborne, Defense of Dark Souls 2, New Vegas (especially since I just watched it recently).
I don't want to spread any baseless accusations around, but when it came to the Fallout 3 and New Vegas videos it seems like he just took entire arguments from 'tismposts about the games on various imageboards wholesale, synthesized them, got footage to show the arguments and made a video out of them all.
Even if he did do so I'm not going to call him a plagiarist or take it as a black mark against him or anything because it's a fucking Youtube video about a bunch of dumb videogames and not a scholarly article about Boccaccio's
Decameron. I know that him and his fans think he's some big-brained high-brow culture critic or whatever churning out his feature-length videos, but for his benefit I'm not putting him up to that standard and besides even getting that much research and content to make a video of that length isn't an easy task.
Now, the Bloodborne and Dark Souls 2 videos... both are full of nonsensical arguments, contradictions and seem really haphazardly put together. The former is obviously not controversial because saying that Bloodborne is genius is preaching to the choir and if you were to play devil's advocate and try to find flaws in the game you'd really have to start reaching, nitpicking and grasping for straws after a certain point since the game is very robust on all fronts.
The defense of Dark Souls 2 one on the other hand was a controversial opinion and seemed like it was his emotional outburst sparked by matthewmatosis' video on Dark Souls 2. It was horribly put together, the arguments were weak and there were contradictions out the ass, so much so that I honestly thought that Harris made an elaborate troll the first time I watched it. On the contradictions part, the things that made me think that he was trolling at first was when he talked about how unforgiving healing was in Dark Souls 1 and how it sucks to die when you heal and how it's oh-so better handled in Demon's Souls and Dark Souls 2. In the Demon's Souls part of the argument he shows himself get impaled and killed by a Knight as he tried healing right in front of his face, in the Dark Souls 2 part he used some clip which seemed tailor made to show how fucking slow your character chugs the Estus which makes the Dark Souls 1 Estus chugging seem lightning fast by comparison. The other one was when he said that the Souls games are "vessels" for 1v1 fights against an opponent on equal footing. Now I could be pedantic about this and rightfully claim that no 1v1 fight in the game is truly against an opponent on equal footing save PvP invasions, but I know what he meant by that, he just likes 1v1 fights against big dudes in armor. Now when he talks about muh "equal footing" he shows footage of the Artorias fight and when he says that Artorias moves and fights like a player would, on screen you see Artorias doing a double front flip in the air followed by slamming a massive two-handed sword on the ground one-handed. Then in another part of the video he goes completely against his whole argument he was building up about Dark Souls 2 being tailor-made for 1v1 fights by going around and defending all the bullshit gank spambush encounters you get showered with throughout the game as well as grasping at straws by defending all the gank'n'trashmob boss fights which are so bad that nobody defends them, not even people who like the game. Examples being Non-Respawning-Enemy-Tier Magus and Trashmob as well as the Skelly Trashmob Lords and The Mohawked Rat and his Rat Trashmob which are so crap you could start playing the Capricious Wind track from Dynasty Warriors 8 and if it weren't for the stamina bar and the absence of your character saying "I DEFEATED AN ENEMY OFFICER" you'd swear you were just playing a musou game.
But my 'tismpost is getting long enough already and I think I made my point clear.