It's not like Matthew's arguments become any less weak for having been presented how he presents them.

They do become more weak when they are misrepresented, hence the "condescension and dishonesty". He shows a clip of Matthew trying to backstab an Ironclad Soldier which results in him getting slammed to the ground, making fun of Matthew for being bad at the game when "his Dark Souls 1 tactic doesn't work anymore". Only if you actually go and watch Matthew's video he was pointing out their slam attack as a positive, not a negative (he was critical of their infinite tracking).

who cares how he makes his arguments when the arguments themselves are solid

When he isn't wasting people's time making fun of Matthew's gameplay he's making these sort of arguments:

If I was to grade all four games healing methods I would put Dark Souls last here, because I don't personally think its method of attrition is all that fun when it comes down to it, and the precise amount of time it takes to heal and the way it immobilizes you, makes it always a tantalizing risk you think you might be able to make, which means more players died trying to heal in this game than any other.

If that's what you call a "solid argument" then that's great for you, but that's just bullshit to my ears. He's literally saying that Dark Souls punishing you is bad. Let that sink in for a moment.

There's also the whole fact that he played the SotFS edition, while he's criticizing Matthew's vanilla thoughts. There's many many things that were wrong with the game that he never experienced, such as the hitboxes. You can't tell someone that he's wrong if you only played the fixed version.

It's been months since I saw the video, so I don't remember much of it, but you must be extremely gullible to buy into this guy's shit.