Is history written by the winners?

To my knowledge, this popular adage has two related meanings:

i) The losers never get to tell their side of the story. History books are written by the winners, from their own slanted perspective. Their self-congratulatory version of events is the official story. 

ii) The winners cast themselves as the heroes and the losers as the villains. The winners depict themselves in the best possible light, and the losers in the worst possible light. 

This adage is used to preemptively discredit historical knowledge. Used to discredit Bible history and church history. But is it true?

i) The Bible doesn't portray Jews and Christians in a very heroic light. The Gospels depict the disciples as obtuse, incredulous, and cowardly. The NT letters generally present churches in a state of moral and/or doctrinal crisis. The OT depicts the Jews as incorrigibly corrupt. Constantly backsliding into paganism. There's a righteous remnant, but that's in the distinct minority. 

ii) Josephus wrote two very influential history books. Was he one of the winners? To the contrary, he was defeated by the Romans. He wrote to rehabilitate the image of the Jews in Roman eyes.

iii) There's a difference between not allowing the "losers" to tell their side of the story, and not preserving their side of the story. Christian monks weren't motivated to copy and recopy books by heretics. But that's not the same thing as suppressing their literature or destroying their literature. 

iv) Let's take another historical comparison: the Civil War. Certainly, the winners wrote accounts of the war. For instance, both Sherman and Grant wrote accounts of the war. 

That, however, doesn't mean the losers were prevented from telling their side of the story. For instance, in the 1880s, Jefferson Davis wrote two accounts of the Civil War. So it's not as if the Confederates were censured. 

Likewise, perhaps the classic history of the Civil War was penned by Shelby Foote, a Southern novelist. Admittedly, that was long after the event. 

v) On the other hand, it's striking that Lee never wrote an account of the Civil War. But that's not because he forbidden from doing so, had he so chosen. 

To some extent we can only speculate on why some participants wrote about the Civli War and others did not. 

a) It's more fun to write about winning than losing. What would Lee write about? How I Lost the Civil War? Not very inspirational. 

b) Dabney wrote two books about the war effort, but that was during the war. That was to kindle support for the war effort. 

c) From what I've read about Lee, I think one reason he didn't write about the war was that he was too demoralized. In addition, he probably had his fill of war. 

d) I expect Davis wrote about the war to rehabilitate his tarnished reputation. To my knowledge, he didn't have much respect from either side. He was viewed as a weak, ineffectual leader. 

By contrast, Lee was lionized by Southerns and respected by many Northerners (although Frederick Douglas had a decidedly less exalted view of Lee). So he didn't need to rehabilitate his image. 

The larger point is that losers often have a chance to tell their side of the story. Whether they do so is up to them. And in the case of Bible writers, the self-portraiture is often far from flattering.