Whenever I hear someone say "rubbin' is racin'", I think of these giants, the risks they took, and the prices they paid. I doubt nerfing others out of the way was part of their strategy in these fragile machines.
Hard to know where the myths end and reality begins, but it's worth remembering that Nuvolari was introduced to Americans by Ken Purdy, in his book Kings of the Road, that bible of we teenage car enthusiasts in the 1950s. And Purdy was quite a mythmaker.
Nuvolari was an amazing driver, no doubt. But I have a very hard time respecting anyone who drove under the Nazi flag. He and others were not just drivers but used extensively in the Nazi propaganda machine as evidence of the superiority of Hitler and the Third Reich.