Netcat was online during Crash 2.0. The technomancer in the Unwired chapter that specifically mentions he wasn't online is Inbus (the dronomancer guest poster). He was hiking in the mountains when that all went down.
Another major difference between otaku and technomancers was the need for an otaku to still need a datajack to connect. Yes, this can be taken as because back then there was no wireless matrix... except the matrix inside of Deus' arcology WAS wireless-enabled (it's how the drones were controlled) and the Whites still needed their jackpoints.
Just as there were spike babies before the Awakening (kids born as elves/dwarves in areas where mana surged upwards a bit early for those unfamiliar with the term), there could just as easily have been otaku that made the jump in the right environment (such as a White, or the test subjects in the zombie rooms, bootstrapping to full-on technomancer white inside Deus' arcology).
The folks that became technomancers as a direct result of Crash 2.0 were those caught online (prolonged, inescapable exposure to the raw matrix... similar to those held prisoner in Deus' zombie rooms). Unfortunately, they got mixed in with the folks for whom being caught online made them stark bonkers (and there's naturally some overlap there). After that initial jolt, others became aware of abilities they very likely already had potential for as the wireless matrix became more widespread.
