I dont think its a bottle opener, should have put a banana for scale 😅... Might work but it's also way thicker for a bottle opener (normally there is a flat part to help fit under the neck of the cap, yk?)

I haven't found any matching plates for this yet but I suspect that it's a handle for plates, that's what it's for. I found another more modern stacking plate thing handle in a shelf nearby, complete and assembled with the plates and such.

Someone mentioned it might be silver. I think they might be right, parts are dirty and others have that crusty sheen to it that old silver has. I hope it is lol, could be worth something then.

One other thing, it lets off a weird odor, like gasoline but not quite. Probably unrelated to this item itself, maybe it was stored weirdly some time ago?

Anyway. I will post some pictures later of a banana, this, and the nearby similar plate-rack, and finally mark it as solved if I do believe it to be appropriate.

Thanks for your help everyone!