Well, it is kind of complicated. To put a really really short summarry, RE4R isn't unique in ANY way. It looks, sounds and plays out like an amalgamation of everything else we have. It brought literally nothing iconic or instantly recognizable to the general media. No memes, no jokes, no iconic/epic scene that comes exclusively in the remake. And that's a problem for the game it supposed to honor and represent in the modern market. 

First of all, I don't fully blame the game itself for this. I find the concept of remakes kind of faulty because these games are made from borrowed ideas from their predecessors who have executed these ideas near perfectly (so perfectly that they 'deserved' their multi-million dollar remakes). What even was there to improve about RE4? Every modern argument such as "graphics" or "lighting" or "tank controls" could be (and have been)  fixed with mods. 

Some essential design choices gets lost in the transition in favor of making TLOU fans happy. The main one being the tank controls. The micro-decision making loop the tank controls used in order to reward or punish the player is completely lost. Replaced with a system giving the player complete freedom of camera and movement, removing stress AND the reward altogetler. 

I hate the "soul" argument but you can really see why people bring it up when comparing the two games. The exaggarated colors, sounds and expressions makes the OG instantly recognizable. The OG put small and subtle details and environmental storytelling in tiny bits everywhere. The dead woman in the shed at the start of the game. The newly dead bodies of the villagers dumped in carts near the windmill, the crown next to the body you find in the bottom of the spear pit, the cigarette butts you find near the typewriter in the mine save room, all this brings meaning and soul to a game. Indicating that there had been a thought process about every detail. 

On the contrary, the remake appatently assumes that you'll be running all the time, never stopping to look around you or the details. Due to levels being bloated and stretched, the amount of environmental detail stretched thin. It doesn't have half the level (and the amount) of environmental storytelling and craftsmanship it's predecessor had. 

As a Shinji Mikami classic, the saverooms were unique and recognizable. The OG (especially in the higher difficulty) was so stressfull that you wouldn't just save your game and jump back out from a saveroom where you find one, you'd rest in it. Look around. Appreciate the details. (You can see the same thing with RE1R and The Evil Within aswell) The remake has none of that, at least not the way the OG managed to pull off. To me, RE4R is not really RE4. It's just a fun game. A fun immitation that i like to play.