If the statements made gave the impression there was such thought going on I would be more willing to grant this. But, as I said, in the original "dissociated" mechanics post (which was the thing that got the term started to begin with), the author very clearly takes a strong stand against "dissociated" mechanics and makes it clear you can't use them while roleplaying, and that this is the reason why people respond badly to such mechanics.
He then responds with completely unrestrained joy at the Numenera GM intrusion mechanic. He even then characterizes people who might be opposed to it as "allergic" to it (rather contrasting with his own previous very strong criticism of such mechanics), and further states that such mechanics are purely optional, GMs don't have to use them. Which...literally applies to every single "dissociated" thing he complained about in 4e.
Yeah, and? Most theories start out naive and develop nuance over time. Finding out that your initial claims were overbroad or simplistic seems... bog standard, actually.
Do I think that this theory is particularly better than just saying, "Eh, this mechanic breaks my suspension of disbelief," which is a subjective measure, and then discussing why for that mechanic? No, not particularly. That is the real underlying theory when you boil it down. Still, it may be possible to develop a framework around it, and develop more descriptive terms than "suspension of disbelief" or "verisimilitude" which people tend to dismiss out-of-hand.
Also, "it may be a more questionable design" is kind of the problem. As a tool for game design analysis, it's completely unreliable; it doesn't identify things that definitely need work, nor can its absence be used to infer that a mechanic doesn't need work (since there are plenty of very bad mechanics that are still "associated.")
I don't think it's useful or practical to only use tools that are reliable. Perfect tools are nice, but perfect tools are not common. Heuristics exist because unreliable tools are extremely useful and often more potent than the alternatives because they better fit the real world.
Code smell is something that comes up quite a bit with programming, for example. The presence of certain patterns doesn't mean that code
is poor, but it does suggest where code might be poor or might have issues in the future. It's called code smell precisely because it's an imprecise and even sometimes wholly subjective measure largely based on experience.
Key question, which I'll keep short to avoid my usual logorrhea: Why doesn't it make sense? If it were magical, would it then make sense?
Well, that's the whole problem with magic, isn't it? Narratively it can always make sense because magic can do anything it wants to. That doesn't mean that fighter doesn't need to make sense, though. If anything, it suggests only that wizard (or magic) need a harder system to work within to define it's limits. Given the open-ended nature of the game world in TTRPGs (as opposed to board games or CRPGs) I don't really think that's practical. Although some open-ended magic systems do exist, they're more pain than they're worth, IMX.
On a wider angle, no, I don't think Vancian casting like 5e particularly makes much sense. Why is how far you can fly in a given day limited by how many goblins you've killed in your life? You don't even have to have killed them with magic! Historically, the magic system felt unknowably incomprehensible. "Wait, I memorize it, and then when I cast it, it's
gone from my memory? How does that work?" It was bizarre and arcane, so it kind of made sense, but it was also before TTRPG game design took off. Magic still works that way, but it basically still doesn't make sense. I've definitely read posts by people playing CRPGs using D&D rules for the first time getting confused why magic works like it does. I don't think making a computer game based on tabletop rules does it any favors. It's all the weight of the tabletop system, and now you've got to invent conveyance for all of it.
And, sometimes, such discussions are interesting and worthwhile. Unfortunately, I find that far too often people take these and do exactly as the Alexandrian did, turning them into "X is bad for objective reasons," rather than "let's have a chat about this and what implications it might have."
I find that it's better to assume that, absent the literal presence of some deductive or inductive proof or citation of the same, any claim of "objectivity" is merely a rhetorical device to express the conviction of the author's beliefs rather than any soundness of the reasoning. That's a safe assumption in virtually all scenarios. Very, very few things are ever objectively anything at all, especially when it comes to something as foundationally subjective as game theory in TTRPGs.