I guess what all of this really boils down to is the original absurdity of the G1 comics and cartoon making the Autobots and Decepticons able to live for millions of years in the first place. The whole reason the Ark was stated to crash-land on Earth "four million years ago" was to allow the ship to crash at a point in history long enough before the northwestern United States had any people in it so that the ship would remain completely undisturbed by humanity until Mount St. Hilary erupted in 1984, woke up the Ark's computer, and reactivated the Autobots and Decepticons on board. That backstory didn't need a four-million-year-long time gap to make that happen. All that was needed was a gap of about 12,000 years since it was a little less than that prior to 1984 when any Native Americans in the northwestern U.S. first turned up in that part of the continent. Granted, 12,000 is still a pretty big number, but nowhere nearly as ungodly HUGE as 4 million. It's actually 333.33 times less that amount.