I know that with New Super Mario Bros. DS, emulator runs are allowed along with official releases such as the physical game and Wii U Virtual Console. Wouldn't it also make sense for it to be the same with New Super Mario Bros. Wii? A section for Console Runs, and a section for Emulator Runs? The main thing here is that I’m not gonna have my Wii with me while I’m in college, and I still want to speedrun this game and be able to submit to leaderboards.

While I can't say for certain, I'm going to take a shot in the dark and say that it's because of a lack of interest. Most people are happy to just record their Wii game play, even if they can only do that with a camera, so there's not really a point to adding an emulator category. Also, a Ds is quite a bit harder to record footage for than a Wii, so it makes sense that some people would want to play on emulator.

We've got this discussion in the past and it's not gonna happen.

Also taking the nsmbds leaderboard as your primary argument isn't enough to convince us. Each community is different and each community have they own point of view about emulator.

You're feel free to speedrun the game on emulator though, it's just you can't submit. Peoples tend to forget they don't need a category on the site to speedrun something.