Here's my take on it:
In the 90's the majority of pro riders used PEDs.
Using PEDs was considered normal amongst the riders.
In their parallel moral world, using was not immoral, but talking about it openly, or if busted was. Within this context Lance was the same as everyone.
With his TdF win, Lance was the catalyst for unprecedented amounts of money being brought into the peloton. Many people got richer as a result of this. Getting off that gravy train became harder and harder because so much money was involved. By the early-mid 2000s there was so much money wrapped up in Armstrongs participation, tv rights, commercial sponsorship etc, that Armstrong and Bruyneel were able to corrupt the UCI, who may have been willing anyway. With every TdF win, Armstrong's house of cards got bigger. Then he retired. Along the way he starts a cancer charity, because he is a cancer survivor and may well have some sense of altruism, plus it makes for great PR, and adds another floor to his house of cards. Remember, within the context of pro cycling Armstrong is not any worse than anyone else, in some respects he is a victim of his own success.
In 2006 Landis got busted. Who was Landis anyway?