Apple is slowly declining (a percent per year) their market share (they are no longer number two - oppo/oneplus has that position now), next year they won't be number three (Huawei). What happens when they go below 10%? Will developer still deliver applications for OSX? Is there a possibility for the same scenario as it was in the Mac vs PC?
Reality is that modern Android mobile phones are good enough for most. Unless you're really into the status symbol part of the Apple, they really don't have something special. Plus there is no need to upgrade a phone anymore. I bought my Galaxy S8+ a year after lunch (much cheaper) and would replace it only because of consumerism - to get a new phone. Arguably there is nothing that really warrants an upgrade today.
Headphones, while a great move, won't help them in a long run - not enough margins and good competition. The silver lining with Apple is the that they have a growing services business. Too bad Netflix is kicking their ass in video content wars. Siri is also mostly mediocre. Homekit - who knows, what happens if your market share is falling.
Reality is that Android won 3 years back. We'll see if Apple can turn around thanks to their endless coffers of cash. It's not over yet, but they need to do something and not just upgrade what they have.