There are a lot of RPG's that don't use Experience systems, but their goal is a clearly-defined progression, perhaps through equipment, skill points, etc. I'd argue Vagrant Story rather cleverly uses these systems and is an RPG consequently.

In most entries barring II and BotW, Zelda isn't an RPG because new gameplay elements are usually handed to you more or less as the plot allows it, Link can choose to forego his skill in weaponry to be better at say, diplomacy? Stealth? Not really. There's elements there, but there's no way to really translate a majority of Zelda's elements to a tabletop role-playing game. Dragon Quest and Final Fantasy were inspired by Ultima, The Bard's Tale, and Wizardry and all five of these series were love letters to D&D, so even though a lot of their mechanics might not be as transparent as in D&D, they're built on a foundation on simulated dice rolls, skill checks, initiatives, etc.

EDIT: I would not be opposed to someone calling Overwatch an Action-RPG for this reason, every ability and weapon has clearly defined damage outputs that can interact with other abilities and criteria and knowing how they interact is not unlike a highly streamlined set of dice rolls and essential to getting good at the game.