Because N64 is the standard and if we allowed emulator and VC for single star, they'd have to have their own leaderboard similar to the standard categories because lag and loading times would mean you'd have to use VC to get the fastest time. Single star is already niche enough, to have a separate leaderboard for emu and VC just isn't worth it.
I'm fine with the decision, but the reason seems arbitrary. Though the mods probably work hard enough as it is considering it's the most popular game so what do I know.
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