The basis of the headline has already been posted here. He put shares into a Roth IRA. He didn't control those businesses legally speaking. If he doesn't touch it before he's 65 he gets the gains tax free.
This is available to all americans. The fact that he did well as an investor is why it's increased to a value of $5bn+.
But hey, Trump supporting Contrarian Billionaire doesn't pay Tax gets a lot of clicks and ad revenue right?