Who's Salla's informant ?
The science for the consumption of the human herd on earth is phoney as is the quality of reality 'leaked' to us from alleged secret programs.
Mental input is not necessary at all with 5th generation artificial intelligence. Artificial Intelligence is logical, and life is logical so to suggest that human stupour has solely impeded ancient and advanced super-technological civilisations is not a story that any of us should buy into.
We know that that cannot be.
ET computing though isn't limited by human issues.