Any particular reason emulators are banned?

Dreamcast emulators still have a ways to go in terms of console accuracy for speedruns unfortunately. Most of the library is playable, but there are still inaccuracies. From what I saw last time I checked, Sonic Shuffle had graphical glitches even on the best emulators and some minor frame rate drops. Since this game is also so reliant on manipulating the computer players and random factors like card drops, it's hard to see the current slate of emulators running comparably to console. That's not to say it couldn't be accepted in the future.