Yes, that might be true. Still, he sure came damn close in 2016. If not for the cheating and the Super Delegates he might have won the nomination.
The fact that he got so close is terrifying. The fact that he was obviously robbed, and chose not to make a stink about it is a good proof point for your assertion: he didn't care that much about losing by cheating, he cared more about advancing his agenda.
He's a true believer. He honeymooned in Moscow. I know for a fact that that was what American Communists were supposed to do. Also, getting married in a Red Dress. Anyone seen Sanders wedding pictures?
He's a sleeper agent.