ok, you're definitely missing the point. They're wildly different cars but very similar at the same time. Yeah they can pull off very similar lap times, but unless you've ACTUALLY driven both of them hard, you have no idea just how different they feel. The 04 STi (with stage 2 susp mods) still didn't feel as good as the Evo does, stock. (granted they've made improvements since then, but that wasn't the point of my comparison). It still does push, even though it continues to rotate. I feel much more confident in the Evo, it doesn't seem to strain quite as hard as the STi does. The fast lap times seem to come easier to the Evo. Simply changing rubber won't make either of these cars fantastically quicker because both tires are basically R compounds.. If you gain a couple tenths here, a couple there, you end up with a full second before you know it. Only a couple tenths per lap around a track is enough to dominate your competition.
All I'm saying is the feel of a car may be all it takes to actually be faster if two cars are so close. Confidence is an incredible tool. You may be confident in an STi, but until you feel the differences, you're simply missing it. Nearly every magazine review says they enjoy driving the Evo more, its simply more fun. I'm not downplaying the STi, I'm just trying to help you understand why the Evo is so popular. Around most circuits the Evo is always faster, and I can now understand why.