Almost every game can be a role playing game by that definition. Zelda games don't have you do anything rpgs have you do typically and the closest it's probably ever been to a rpg is botw because of minor stats like stamina and hot and cold and different weapons.
Outside of that there is no building up a character, customization, leveling up, stats, conversations back and forth or some deep long 60 hour story.
Its you traversing the world trying to stop ganondorf.
It's just an adventure game series with an over arching lore.
Its the opposite usually when you play a character like Geralt or Aloy it feels less like role playing and more like you are just on a characters journey. In zelda you yourself mold link into the person you think he should be, he’s a hollow shell of a character. People talk at him and you form the responses in your head as to what he should be saying.
That is the core concept of the silent protagonist. You get the same thing with Joker, Chrono, Ness, Ryu, etc. the purpose is that they are a vessel for the player to experience the world. Role playing isn’t only stat building and dice rolling.
Also, a lot of stats in rpg games are superficial metrics for progression anyway. At the end of the day Witcher 3 and BoTW share the same progression only Zelda hides the numbers. You are still getting better armor, higher damage dealing weapons, elemental effects, more health (hearts instead of HP), more stamina, you’re still exploring, going into dungeons, crafting, etc.
Zelda probably has more in common with your typical WRPG than it does with Japanese adventure games
