That is wrong on so many levels. I grew up in a Windows environment in the '90s tro '00s and had the best video games in the world at my finger tips, while Mac users at the time had what, some high quality photo editing software? Good for them I guess.
So unless you don't count video games as software, Gates was right. DOS and Windows being the main platforms for the hottest videogames of the moment, was what led to the popularity of the PC over Macs at the time. I think Doom alone was responsible for millions of PC and MS-DOS sales.
Yeah, Job's Next-Step machines and SW were cool, UNIXy and all, but to what end if nobody but the wealthiest businesses and institutions bought them in numbers you can count on a few hands? In fact, Jobs understood from the fail of the Next-step and the success of the DOS-PC that you need to get your devices cheaply in the hands and homes of as many casual consumers as possible (hence the success of the colorful and affordable iMac G3) and forget the premium business workstation market.