“Yall are in a cult, and it is TESCREAL.”
So I know you were going for a snappy summary, but I think one of the important things to note is that the TESCREAL essay doesn't call them a singular cult, it draws connections between the letters of the acronym including inspirations, people in multiple letters of the acronym, common terminology, common ideological assumptions, and such.
I think a hypothetical more mature rationalist movement would acknowledge their historical and current influences and think critically about how they relate to them instead of just going nuh-uh. Like the relatively more reasonable EAs occasionally point out problematic trends in their movement and at least try to address them (not particularly effectually, but at least they aren't all in total denial).