Well, he doesn't know. Most of Vinge's works were about getting close to the Singularity without crossing over, because he expected that technology and society would change massively and unpredictably at that time.

The point of introducing the fantasy element of the Zones of Thought was to allow Vinge to write a FTL space opera without having to deal with post-Singularity speculation.

When species transcended, they left the Beyond and went into the Transcend.