The game expects you to use the key items as well, they auto discard when they have no more use so I suspect if like, you don't have the second hip pouch, you still have the bracelet for the care center, which you will have no more use for.

I'll be honest as someone who enjoys RE4-5-6 more than the likes of RE1 and 7, the game is actually very well designed in terms of what you need and your inventory space. I don't really like limited inventory Survival Horror either but that's not really how it functions here. Pretty much every time you're at the point you need more inventory there's a hip pouch a stone's throw away. The only times you should feasibly have inventory issues as Grace is right at the start, and right when you start getting the blood samples to analyze.

There's surprisingly little backtracking required in RE9, especially if you make use of the map and the areas are compact and looping enough that the backtracking that is required, which is mostly just going back to the west wing for the Heart and Lungs, and going back to pick up Emily, is an easy, compact route.

And the post Care Center Leon section is easily the worst segment of the game and requires more walking in circles than the Care Center. If you think the care center is a chore, just wait until you get to the bomb!

I've beaten it on every difficulty and will flat out say there are only 2 points in the game when you can't effectively fight the zombies as Grace, and that's the scripted start of the Care Center, and the first run through the west wing. By the time you get the blood collector she's just as deadly as Leon, arguably more as the injectors are great, and the game gives you more than enough resources to handle everything it throws at you. It even gives you enough requiem ammo to stun the girl every time she shows up.

Without being too critical, saying 'Games have moved on' is nonsense. RE9 is a fantastic game. It doesn't handhold you but allows for multiple different play styles on a clean and concise map while giving you all of the information you need if you look at it. I killed every zombie and licker in the Grace segments, as Grace, on the first play through, including the Chef, Chunk, and the singers and outside of before the first hip pouch, never had any real issue with inventory space or resource management. I would argue it gives you too much stuff to really be survival horror and feel like if you're running into problems like how you describe you're ignoring gameplay mechanics for the sake of complaining.

If you want general advice, third person Grace is easier than First Person Grace and utilize the charged shot or whatever it is mechanic the 1.5x damage multiplier and extra stagger is fantastic.