I understand where you're coming from and see it or try to see it from your point of view. However, re-builds do not guarantee anything. There are alot of teams that have been rebuilding for 20 years.
Like who? What teams recently have been rebuilding for 20 years?
There's more teams stuck in "purgatory" over/under 3 games .500 than actual tanking teams. Nowadays it only takes a few high pick years in a row to flip the trajectory of your franchise.