I've stated that they are like extra attacks, and seem to be clearly intended to parallel the number of attacks a fighter of the same level would get.
The term "appeal to authority", as a logical fallacy, refers specifically to using "but someone important said so" as a replacement for an argument. But it's not a fallacy in the case where the authority genuinely has authority to answer the question. If you're not Catholic, you might consider it a fallacious appeal to authority for someone to say "the Pope says..." on a moral issue... But it's not a fallacy to point to what the Pope says when talking about Catholic doctrine. If Jeremy Crawford does indeed make a statement about the intent of the rules, then it's a valid authority to cite to. But as of yet, I've seen nothing from him on the specific questions I think are meaningfully disputed.
Also, thinking more about the AMF thing, it seems to me that "a trap which is described as going off immediately when triggered" is a better way to think about the timing questions of the eldritch blast ways, but useless for discussing readied actions, as traps aren't readied actions.