wiley didnt appear out of nowhere. there were precursors and contemporaries all of whom deserve a mention. But at the same time if you can only see the continuity and not the ruptures you're only getting half the picture. Even when I first heard Wiley (with Riko) in '98/'99 on a drum and bass station i was shocked. It was different. Not so much in terms of form but because of what they were saying. From there I knew things had changed and all traces of rave utopianism were dead.
Speaking musically I'd identify two ruptures. One was eskimo, which sounded like a bolt out of the blue and nothing like the sublow and 8 bar that came before it even if it took cues from the spartan, hard edged architecture of those early tunes (and things like the4x4 Harry Lime stuff) and one was wiley and dizzee clashing so soild on choice. Straight away so solid seemed old hat. They were still doing the 'garage voice' grindah parodies on people just do nothing.
Eskimo, and other tunes out that camp (the Danny Weed stuff for example) have an off kilter, staggered quality you dont find in breaks or anything that had come out of garage. The devil mixes took the experimentalism even further. Wiley's bass sound was unique and had zomby doing piss poor impersonations of it 10 years after the fact.