It's just a theoretical raw performance. Additional effects like anisotropic filtering or shading lowers that number dramatically. Besides, some gamers don't have modern graphic cards.
Does FO use anisotropic filtering or shading?
And isn't anisotropic filtering for textures?
If you are talking about gamers that don't have a modern graphic card, then I'm one of them. My card is 6 years old it's one of the weakest of the nVidia 6 series (GF 6200) stuck in a AGP x4 slot.
Today I've made a small demo, just one mesh, 2 lights. The mesh is a subdivided teapot with ~700 000 triangles. Through the fix function pipeline (lights per vertex) I get 53 FPS, with a shader (per pixel light) 52 FPS. If you don't believe me I can provide the demo.
I don't want to undermine the project, or even criticise the models, some of them are great. They could be fantastic as a low level LOD (for max zoom-out).
I'm just saying that the polygon budget is outdated by 10 years. I know what I'm saying I'm a game dev myself, a beginner at it but I've done my math, I've done my homework I know how it works.