I guess a better thread title is why didn't the Jedi rebuild COMPLETELY, though we've all covered it more or less. The enclave was rebuilt enough so that the order could establish itself once more "when the time was right". Unfortunately it was short lived. IMO the only place that actually got rebuilt was the council quarters and the door. The rest of it was pretty much ruins though the underside to the academy seemed fairly intact.
"I cant see S***! --YOU GO TO HELL!" --Tourettes guy