That neither can be sufficient for truly getting to grips with Thatcher's legacy on a personal or political level, is evidenced by the fact that both arguments can just as easily be used as apologia for her old friend General Augusto Pinochet.
Further comparisons would of course take us into the realms of the absurdly overstretched.
Thatcher, for example, did not have the nation's leading literary light extinguished (probably), and then send a bunch of jackbooted thugs to ransack his house and burn all 8000 books in his library. Etc.
Yet we all know that even Hitler can chalk up VWs and dangerous roads in his plus column.
The fact is that strong, manipulative and ultimately abusive government tends to emerge out of periods of disfunction. Look back through the last few hundred years of history and when you find an authoritarian you can nearly always find the clusterfuck that immediately preceded them. Disarray legitimises dictatorship.
Historians are often tempted to characterise the emergent leader as a sort of aberrant opportunist (right place, right moment etc.), but perhaps there is nothing more natural than a system finding a way to unclog itself after it has become a bit bunged up under a previous configuration.