Roman Reigns was the Universal Champion for four years, and during that time, he changed the business. Reigns is still seen as the face of the company despite not being champion for almost a year, so he likely took offense to not being offered a role by The Rock.
The Final Boss showed up on SmackDown to make an offer to Cody Rhodes to become the corporate champion, something that he could have offered Reigns last year or even offered him now since he believes he will win back his title at some point.
This offer could cause some serious issues between Roman Reigns and The Rock after the two men were on the same page back in January. The Final Boss acknowledged Reigns by placing the Ula Fala around his neck after he won the Tribal Combat match.
Reigns wasn't in attendance for SmackDown but it will be interesting to see how he reacts to the news that Rhodes has been offered this position while he was on hiatus after being injured by Seth Rollins.
It's unclear if Roman Reigns will be in attendance for Elimination Chamber. But, the likelihood is that if he is, he could crash the promo between The Rock and Rhodes and make it clear he's not behind this new direction for his Bloodline member.
The Tribal Chief and The Rock are expected to go one-on-one at WrestleMania at some point and a feud could likely start in the coming weeks and then build over the next year.
Reigns is a face now, so he wouldn't have accepted the role if it was offered, but he would have liked to have been offered it by his own family.
If Reigns is hurt by The Rock's decision then he could shun him from his family, which would lead to much bigger issues between the two men in the future.