There's no reason for the UCI to strip all 7 victories.
AFAIK, the only physical evidence of LA doping was during the '99 tour and it was only discovered years later when they had an effective test for EPO. Not saying that he didn't dope for the other tours, just that there's no physical evidence of it. Without that, or an admission of guilt, there's isn't much anyone can do. This isn't like asking Rasmussen to leave the tour in 2007 due to strong suspicion of doping (or lying about his whereabouts during out of competition training). You're talking about rewriting history here, and if the UCI does that for Lance, they'll have to do it for almost every TdF winner going back 60 years.