The current definition of RPG i honestly don't get it.
Things just have expanded now. Definitions get looser as a wider audience is exposed to something.
Taken as the straight definition of the worlds "Role-Playing Game", anything similar to a visual novel, where you play the Role of specific characters, can be called an RPG.
But the graphics, attention to details, and proliferation of systems have crossed over a LOT now. Stat-based gameplay is no longer locked to a game with top-down strategic maps, that "zoom in" to show a second, newly draw set of detailed characters VS enemies, all contained within a turn-based, D&D derived system.
The stuff one does in Monster Hunter World is basically the same as one does in an Ys game. The only real difference is where the camera is focused while you play. The cinematics even feel like an evolution of what one would have seen in FFVII years ago.
Zelda is typically seen as an Action RPG series, but there's a lot of gameplay that it shares with something like Lost Planet, or a Resident Evil game, now. Shooters have damage numbers and status effects. Playing an actual defined role has spread to almost every gaming genre in existence. RACING GAMES have stories, and a cast of characters to meet now. The boundaries have definitely widened, and the differences have started to disappear.