Steve Jobs gave Woz half of the base amount, which is what Woz agreed to. Jobs withheld the fact that he was going to receive a bonus on top of the base amount, and did not share any of that money.

Was it an ethical mistake? Sure. He should have at least disclosed that he was receiving the bonus money, even if he didn't want to share it.

But claiming it was a "major ethical mistake" seems fairly out of touch with reality.

And of course, taken in the context of all of the good things they did together, it was completely insignificant and Woz has said as much.