The iPhone is still Apple’s most important product, and it’s not remotely close. Don’t get distracted by all the people pining for a car, wondering what Apple’s AR headset might look like, claiming the iPad is the computer of the future, or wishing Apple would go ahead and build a TV already. The iPhone still accounts for most of Apple’s revenue, and iPhone users — who also pay for iCloud and Apple TV Plus and buy cases and cables and headphones and smartwatches — account…