Remind me who history is written by.
For example, the article says that if Churchill had not been thrown out of power at the end of WW II, his history of that war would never have been written. I'm not sure that's actually true--Churchill had done plenty of writing before that and probably would have found time to write such a history later on anyway. But even if it's true, it doesn't mean that we would be without any history of WW II if Churchill had remained in power. There are plenty of other histories of that war, including ones which take very different viewpoints from Churchill's.
But even leaving that aside: yes, Churchill "lost" in the sense that his party lost the election in 1945. But that does not make Churchill a loser in WW II itself, nor does it make his history of that war a history written by a loser. Indeed, his history of WW II, as far as I can tell, says nothing about his loss of the Prime Ministership or the party that defeated him. It talks about his own leadership during the war, which, at least as far as keeping Britain from being conquered and reclaiming Western Europe was concerned, was a victory, not a loss.
The example of Thucydides also isn't as simple as the article makes it out to be. Yes, Thucydides was originally an Athenian and fought on the Athenian side, i.e., the side that would eventually lose, in the Peloponnesian War. But Thucydides was exiled from Athens long before that war ended and Athens fell from power--and where did he settle? In the Peloponnese, i.e., in the domain of Sparta. In other words, he wasn't writing his history of the war as a losing Athenian. Sure, his portrayal of people he personally interacted with, particularly people he lost battles to, is going to reflect his own interests, but that's not the same as the entire history being a history written by a loser.
Even the article's main example, Sima Qian, isn't that simple. The article makes it seem like Sima Qian's history was mainly about the emperor who had him castrated. But his history actually covered more than two thousand years. Whatever is in it regarding that one emperor is only a small part of the whole. (And it's arguable that Sima Qian didn't even end up as a loser in the Chinese court of his own time; after being released from prison he had a highly paid job as a palace eunuch.)
> We say that history is written by the winners. That is sometimes true.
Also wasn't it shown in a black and white film of one Shakespeare's plays (Henry V?).
A knight actually beats a soldier (who is carrying a similar weight and 10 years his junior) across an obstacle course in this short film 'Obstacle Run in Armour': https://www.youtube.com/watch?v=pAzI1UvlQqw