Mine is a plain theory that's based on the facts we have, a guess. I make no claim that I know for sure. A conspiracy theory is that there's a secret conspiracy against us. Jumping rashly to "they're hiding it all man there's something going on man" is a conspiracy theory.

Occam's Razer. The simplest solution is pro ably the correct one. They probably overwhelmed their ancient hardware with new tech. Which happens to line up pretty well with what was said and what we know.