If you had millions (much less trillions) in income to stash overseas, you wouldn't go to jail for it, even if it was flagrantly illegal. People don't go to jail for white-collar crime, generally.
If he'd paid a fine after they caught him, he wouldn't have gone to jail. He very openly refused to pay. He effectively went to jail for refusing to pay a fine.
If you want to go to jail, try shoplifting.