ISS recommending a vote against approving senior management pay packages doesn't happen very often. So its move shows institutional holders (who, due to Apple's market capitalization and widespread presence in various benchmarks and indices, own the vast majority of AAPL) may actually be feeling some real dissatisfaction with Apple's executive compensation levels.
Personally, as an individual holder of AAPL, I think that Apple's Board of Directors needs to be completely overhauled. Most of the Directors do not bring any real business value to the table and/or have, to put it generously, mixed records in running their own companies. Apple needs a board that challenges and extends what Apple's managers propose, not one that merely acts as a rubber stamp.
In any case, shareholders who feel strongly one way or another about anything that is up for a shareholder vote should take the time to fill out their proxies. You're an owner, after all! Plus even if a specific measure does not gather enough votes for formal approval, companies sometimes still take the recommended action if a meaningful percentage of shareholders vote in favor.