Almost all human societies and planets in the Pegasus galaxy are technologically quite primitive. The few exceptions we see, notably the Genii, and the Hoffans, go to great lengths to hide their technology and scientific progress from the Wraith. Each of these societies build hidden underground bunkers to preserve personnel and scientific knowledge.
However, the Satedans seem to be technologically comparable to both the Genii and the Hoffans. We see their weapons technology in the episode Sateda (in flashback):
Further, in the episode Runner we see that the Satedans built large above ground cities:
So, why did the Wraith allow the Satedans to develop technologically? Their technological development was obviously not sufficient to survive a Wraith attack, but it was sufficient to make wiping them out a serious endeavor.