No...you can't go backwards and do amateur boxing after doing pro MMA. I wish I could amateur boxing tournaments would be a fun thing to try but I would have to fight pro boxing and pro boxers are a different level of punchers then MMA fighters.
Yeah true, it's night and day, even compared to Kickboxers/NakMuay. And the head-start is too big.
Ray Sefo is a six-time Muay Thai World Champion and got trashed by what the boxing community viewed as a "can".