I think it was simply his don't give a fuck attitude toward authority. I think most everyone would like to thumb their nose at 'the man' but most don't have the balls to do it.
Literally every criminal that didn't rat or accept a plea deal has done this very same thing, from mobsters to 7 Eleven robbers. Gotti looked more like a Wall Street shark than a mobster. The bosses in the commission trial looked like grandparents. Gotti looked like Gordon Gekko. The media took to him, gave him a rebel status by calling him "The Teflon Don", and made him a star.
"...the successful annihilation of organized crime's subculture in America would rock the 'legitimate' world's foundation, which would ultimately force fundamental social changes and redistributions of wealth and power in this country. Meyer Lansky's dream was to bond the two worlds together so that one could not survive without the other." - Dan E. Moldea
