There is a lot more truth to it then you give credit. True Atari was already in trouble for a number of reasons, but that huge wet fart called ET was indeed a huge ****ing nail in the coffin. Atari hedged their bets on it and paid millions for the naming rights, it also led to a big downturn for Atari in the industry. Then the Japanese came in and finished them off slowly, but surely.
Ever hear of a game called Pac Man?