Writer Rhyu Si-min is not attacking the President.

First, it is beyond my knowledge whether his claims are based on verified facts or are merely his own speculations.
One would have to enter his mind to know that.
However, it seems clear that Writer Rhyu Si-min has decided to attack the President—who has been biased against the "Moon-jo-teol-lae-yu" group—as a way of responding to the all-out attacks directed at them.
The group referred to as "New Lee Jae-myung" represents the figure of the President according to their own preferences to claim loyalty, and that loyalty manifests as aggression toward the pro-Moon group, which they perceive as the opposition. However, their method of attack is so infantile and low-level that it actually obscures the essence of the logic they are criticizing. The indiscriminately used "anti-Myung" frame is a result of this.
Because they simplify the target's arguments, trap them in frames biased by their own preconceptions, and treat the opponent solely through ridicule, the entire discourse collapses to the level of Ilbe-style rhetoric.
The loyalty toward the "represented" President, which serves as an outlet for the aforementioned "New Lee Jae-myung" aggression, could actually be a good point of attack from the perspective of the "Moon-jo-teol-lae-yu" group. I believe Rhyu Si-min was trying to seize that point. I also believe that Rhyu Si-min, as he claims, is not certain whether the President orchestrated all these phenomena.
However, to silence the propaganda of the "New Lee Jae-myung" group, which occupies the majority of the YouTube media ecosystem, it is effective to attack their emotional leader, which is their vulnerability. Instead of a top-down bullying method, using a bottom-up "reverse-bullying" approach to force responsibility onto them—regardless of the actual facts—can have the effect of forcibly dispersing the overall energy of the attack.
At some point, people end up forgetting who the actual cause of this phenomenon is.
Regardless of the truth or sincerity, I believe Rhyu Si-min is performing his function and role. He can be seen as a fierce strategist.
Therefore, they shouldn't have initiated such childish attacks in the first place. The frame that the "Moon-jo-teol-lae-yu" group is obstructing the President's administration is merely a cognitively distorted delusion of the "New Lee Jae-myung" followers.