Pre-cancer Lance Armstrong was a great one day racer which I would compare to a worse version of Julian Alaphilippe or a better version of Jacob Fuglsang in terms of what he could achieve in one day races. I do not think it is fair to compare his one day palmaries without taking into account that after the cancer he was effectively not racing any of those, hence any wins or achievements are in short period when he was pretty young. Especially, considering that during those times the cyclist would usually peak at older age then now due to lack of training knowledge at lower levels and other factors. That being said, I would not call him a generational talent based on what he showed pre-cancer, even if we were to extrapolate expected wins/palmaries based on the first part of his career.
As a GC rider, Lance has to be mentioned in the GOAT conversion, again, as a GC rider. Winning 7 TdF in a row is truly special. Pretty much everyone (or everyone that matters in terms of GC competition) doped in that era, so I would call the field pretty level. Yes, some will say that he had better drugs then others, but I do not think the difference is such high. I think the biggest difference was his drive and willingness to do whatever it takes, including investing into his own success by ensuring that he has the best doctor, the best drugs and training. In comparison his contemporaries like Ulrich or Pantani do not looks as driven or as focused compared to Lance. It is also likely that he was a better responder to drugs than many other GC guys of the same era, as his VO2max (reportedly in low-mid 80s) is exceptionally good but not extraordinary, ie not generational as LeMond's (90s) and probably few others. We also have to take into account that there in cycling vs running there is somewhat more direct relation between VO2max and performance, although, the best marker would be power at threshold.
Obviously, when discussing Lance, it has to be mentioned that he is a generational a**hole, that has no (or close to no) regard to other beings if they stand between him and his goals. Exceptionally driven and talented a**hole.