The question some should be asking is not, “Is Apple going to be relevant?” It should be more like “In five years, will I be relevant to Apple?” It depends on whether or not that individual looks at the landscape of the things Apple has created and can say to themselves, “I like these products an their price is worth it for the value I would receive from them.” If so, then the will be.
At any one time, the products and services Apple produces are not made for the entire computing market, they focus on a
slice of it that can be profitable to serve. For the folks in that slice, it feels to them like these products are made for
EVERYONE if only everyone would see it (or if Apple made their products cheaper… which is against the point

) There are folks that, for a number of years, were IN the slice as Apple defined it at the time. And, when Apple redefined it (which they do regularly), some folks found themselves no longer in the slice Apple’s putting their attention on.
As long as Apple can continue to find those profitable millions every year (they’re pretty good at it by now) and continues to offer a mix of goods and services an ever changing slice of folks find valuable, they’ll be ok.