Aubriacbut if I look at the main reason why this whole thing pisses him off I can at least slightly see where he's coming from.
I don't, he's been told this a million times directly. There are ZERO items that were ruined to try to placate competitive players yet they will still cite balance changes that were done for the casual audience as being problematic. He blocks people who give him feedback. Even on streams when he does item votes, if his fans pick something different than him his reaction is "wow uh, okay". He surrounds himself with dickriders like Richter.
He doesn't want to try Newbie Mixes and definitely doesn't want a debate. Having a scape goat is pretty convenient. Even if you are not trying to make a social stand just as a general insult or takeaway for issues.
And if we are being honest with ourselves, while MyM was an utter disaster; the base idea lead to the game being in a much better and ergonomic state. Valve's balancing only got better with time, matchmaking is much more convenient now. Quickplay back in the day was pretty slow and defaulted to Valve servers, anyways. The only stinker that still remains is the Ranked Gamemode (I'm not even going to refer to it as "competitive" because it's not). This is a difficult pill to swallow but without MyM Valve may have gotten a lot more complacent than now but much earlier instead of post blue moon.
This thread is an unnecessarily complex thought experiment for people to realize that there is an absence of competitive youtubers that talk about the scene and talk TO other content creators. That requires them to be semi-active in those circles. You have to appeal to normies, they are the target crowd and you need to talk to them in their language.