The Last of Us is not a role playing game. It is a game that pushed the gaming medium further, with its controversial conclusion. It's not about what YOU would do, it's about what the characters in the game do. The strength of The Last of Us is its focused story telling. What you paint as a narrow "gallery shooter" is what makes The Last of Us have such a strong emotional impact. There is no disjoint gameplay and story, and you've missed the whole point of the game in why you want it to be an RPG. You're saying there are only cut-scenes and shooting, but that's not the case. Just because you don't have any dialog options doesn't mean dialog doesn't happen. And it does. All the time. In gameplay.
The Last of Us pushes the medium forward because it shows us that games aren't only about being the biggest author insertion machine as possible, but rather about telling stories in various ways. The fact that it's an interactive medium doesn't mean that you need an a story you can control. RPG is vague enough as a genre, but there's nothing about the systems one would envision by such a suggestion that would add anything to the game. I would say that you're looking for stories in the wrong places if there's not a living world there for you in The Last of Us. That, or you are too concerned that it is linear.
I wouldn't say that your opinion is wrong, but I do think you should respect what is a critically acclaimed game at the sake of diversity. I don't call for games that I don't feel to change to be more like the games that I do like. I can't get into the Witcher. I'm not that big a fan of the time period, but I won't say that the game should have a sci-fi setting. As such, this is a game that doesn't resonate with you, but it doesn't mean there's anything wrong with the game. The last thing The Last of Us 2 needs is to be changed into an RPG.
See, everything you say should be there is there. The game tells its story through gameplay, through interactions in gameplay. Never before has a ludonarrative dissonance been further away than in The Last Of Us. There's no practical difference between a cutscene and gameplay. Just because the ludo-part of the game doesn't revolve around character interaction doesn't mean that character interaction isn't there. It's like you discredit things that don't come with gameplay prompt or choice. Where you might derive the world from talking with NPCs, The Last of Us tells those stories in details and subtle hints. Things aren't that explicit in this game, but when you look at the details of the game, you see just how fleshed out everything is. Every house you enter tells its own story about the people who lived there. Each set conveys its own story. You have walking down roads with tons and tons of cars that are stranded in a queue. You have people who died while they tried getting out of the city still in the cars. The Last of Us isn't about meeting a stranded NPC along the way that say the lost their pendant that their dead husband gave to them. It's about entering a house with suitcases on the bed, understanding the urgency that went into when that place was evacuated. It's a walk through a world of despair, seeing the carnage it left behind. The story is so densely packed that I'm not surprised it's hard to take it all in, but all of this is just me trying to show that The Last of US works extremely well the way it is set up. Let's leave it like that.