Diaz's account is entirely intended as a defense of his own actions. But he isn't trying to defend himself according to modern standards, at all! He admits that

Diaz's account is entirely intended as a defense of his own actions. But he isn't trying to defend himself according to modern standards, at all! He admits that the conquistadors slaughtered non-military people for all sorts of reasons, took women as "wives" from conquered people, killed people just for believing in a different religion, lied and backstabbed, stole any valuables they could find. Everything we criticize the conquistadors for today, Bernal Diaz isn't even trying to defend. What he spends all this time defending against is accusations that Cortes broke the rules of the Spanish monarchy, and that some other conquistador is actually the one who had the right to plunder the Aztec empire. Nobody really cares about that nowadays. Also - it's pretty clear from Diaz's accounts that the Aztecs did not treat them like gods. There are a couple characters at some point who think they are some sort of monster because they haven't seen people on horseback before. But for the vast majority of the account, the conquistadors are explaining to the locals that they are warriors who serve a king that lives across the ocean, and the locals understand that.