Of the people listed, I think Greg LeMond is the only one, who maintains that Lance Armstrong was at best a mediocre cyclist if everyone was clean. They are not in friendly terms and were never teammates and their professional cycling careers overlapped like a year or two.
The opinion of David Walsh in 1992-1993 was that the low-octane doper Lance Armstrong was a great cyclist that would achieve a lot during his career, but the prevalence of doping changed the story significantly. Tyler Hamilton also speculates in his books that if everyone were clean, Lance unlikely would have won his seven TDF victories, but would've been capable to win one or more. Also despite his personal flaws, his Motorola teammate Stephen Swart considered him one of the greatest cyclist despite later testifying about the EPO use inside the team.
FWIW, Emma O'Reilly has actually recoinciled with Armstrong (and Johan Bruyneel) despite the nastiness from the part of the Armstrong team.
SImultaneously fully true that the USPS focused almost obsessively on the TDF to guarantee that Armstrong won. As has been pointed out, they didn't focus on other team member succeeding, ie. they had no sprint specialists and had more pawns to sacrifice in the course of the race etc.