It doesn't matter what Pereira said about it. Here's what Gene Steratore, whose team made the call said:
"Although the receiver possessing the football, he must maintain possession of that football throughout the entire process of the catch. In our judgment, he maintained possession but continued to fall and never had another act common to the game. We deemed that by our judgment to be the full process of the catch, and at the time he lands and the ball hits the ground, it comes loose as it hits the ground, which would make that incomplete; although he repossesses it, it does contact the ground when he reaches so the repossession is irrelevant because it was ruled an incomplete pass when we had the ball hit the ground."
Except he did, obviously make multiple 'acts common to the game.' And even if you want to debate whether changing hands, pushing towards the goal line with his next step, and extending were 'acts common to the game,' you're still debating. Which means it obviously wasn't indisputable by definition.
It was a catch, a correct call on the field, and a controversial overturn that should not have happened.