The point isn't whether Gates is a nice guy or not; the point is how he was *perceived* at different points in time. In _Hackers_, as was common at the time, he was portrayed in a positive light. If you were around back then, it was IBM that was the "big evil" back then. Microsoft just wasn't seen that way. This isn't "whitewashing" his reputation, it is just reminding us that corporate image changes over time.
We are seeing this today with Apple and Jobs. While Apple was (at least during the last 20 years) seen as the plucky underdog fighting against Microsoft, now that the iPhone is so popular they are beginning to throw their weight around, rejecting apps for seemingly arbitrary reasons and banning cross-platform tools for iPhone development to hinder the growth of competitors like Android, Apple will be seen as the new devil -- and I say that as a Mac and iPhone user.