Something that annoyed me about the finale was Lee's unilateral decision to condemn the survivors of the human race to the Stone Age.
Agreed. Moreover, the idea was that there's a cycle of "Human society builds Cylons, who destroy Humans and build Centurions, who destroy Cylons - restart."
By destroying technology Terrans will never know what happened and just restart the cycle. If, however, the Colonials kept their tech and ships, they could've taught their descendants not to build robots again.