I don't understand

You can submit Glitchless runs to the Level leaderboards.
We just don't separate them out, as there would be many empty boards for glitched.

To add to Ben's point, IL's have always included glitches where possible as the point of an IL is to complete the level as fast as humanly possible.

sonic mania play store opensonic, sonic 3 play, sonic mania play, lego lego mario, mario windows, emulator win 10, retro games nes, prime video gaming, opensonic, ms nes, luigi super mario bros, sonic 2 sonic pc, mario 64,new super mario, genesis rom, vds nds emulator, emulator snes android, snes mario rom, nintendo emulator android, mario kart play, smw, smb 4, smb, 8 bit games,emulator ds for pc