I've got most of my comic books from the late 70s and virtually all of them from the 80s-early 2000s. No way they are worth tens of thousands, and I've boxed most of the ones from the 80s and beyond including Secret Wars, Crisis on Infinite Worlds, Death of Robin, Death of Superman, and just about any major shake up in Marvel or DC.
Even in perfect shape, there might be a handful "worth" money but most aren't especially if they aren't in pristine condition.