N1 got funding in 1964 and had it's first stacked test flight in 1969 (5 years). Starship was announced in 2017 (though the raptor engines in 2016) and had it's first stacked test flight today (5 years). So far development speed is the same, even with SpaceX's better technology.
Whatever technical issues N1 had, could have been resolved with enough iterations. We have no idea if Starship will work and if it does have design problems, we won't know until years from now if it fails or succeeds.
Whatever technical issues N1 had, could have been resolved with enough iterations. We have no idea if Starship will work and if it does have design problems, we won't know until years from now if it fails or succeeds.