So far the comments are explaining why Tim Cook would sit silent instead of doing the right thing: economics. It's the same excuse why they would stay silent on Chinese government abuses.
It's one of the core critiques of capitalism that companies are unethical and profit maximizing, caring only about shareholders, not stakeholders. Kowtowing to liars or autocrats to remain in their good graces is cowardice and enabling and we shouldn't justify everything because it's good for economics. We should hold these public companies to higher standards, and that includes taking actions to get into the good graces of political cronies.
Trump may have been wrong but I doubt he was lying — merely not correctly informed. The exact details of Apple’s supply chain are not something I would reasonably expect the President of the United States to be totally au fait with.
What do you mean? Why would Tim Cook choose to correct the President when it's election season? If Trump loses, it's bad for Apple to be making Trump look bad. If someone else wins, it's not going to be because Apple corrected him. Correcting the President is a lose-lose situation here, so it's best for Apple's CEO to let Trump have this one.
So if Trump decides he wants Apple to make an iOS modification that helps the US government and hurts privacy, and he threatens to lead his supporters against them, bashing them on the campaign trail, would that be ok?
People tend to give Tim Cook a mulligan on China, because quite frankly, President Xi could almost destroy them, but Trump holds no such absolute power over them in the US, and they should be well within their power to push back and correct the administration for falsehoods, whether or not iPhone owners who happen to be Trump supporters like it or not.
I suspect they'll complain, but keep buying iPhones. Very few people are going to change their OS platform because of a political spat.