Managers have extremely wide latitude under the law to run the business as they see fit. As long as they have some hazy explanation as to how their actions could plausibly be for the benefit of shareholders, then they can do as they please. If shareholders don't like that, they can fire the managers. For example, Bezos could certainly say, "We think patents are stupid, as do many of our key customers, potential acquisition targets, and employees we'd like to hire." That could all be hogwash, but as long as he says it with a straight face on the witness stand, I don't believe he can successfully be sued personally.

The only reason eBay v Newmark exists as a case is that the managers are also the majority shareholders, which introduces a conflict of interest. (Well, that and the fact that eBay are dicks who were trying to fuck with a key competitor.) It's a weird case, and that decision has no practical implication for Bezos.

That bit from the decision comes up in regards to complicated stock shenanigans designed to keep eBay from getting more CL stock. The principle isn't being applied to ordinary management decisions, just decisions about stock ownership and board seats. So even if this decision did mean something for Bezos, it wouldn't mean anything about him deciding not to enforce patents.

Somebody else already cited this, and I don't think it proves what you think it proves. In this case, Craig and Jim were sued because they were actively attempting to diminish eBay's share value. In my inexpert opinion, it is not analogous to failing to enforce dubious patents. At any rate, the odds that Amazon would actually have been sued for failing to enforce one-click strike me as incredibly low.