I think that the best description of what is probably going on at Apple is something what is Steve Jobs talking about in that "lost interview" from 1995. He compares Apple to Pepsi to describe why Apple has failed after he was fired. He talks about Pepsi and how it's controlled mostly by marketing people, because new product for Pepsi is like a new size bottle. On the other hand, the technology company is mostly controlled by tech / product people, but when the tech company become a monopoly in some field, the marketing people are the ones who take control, because the company itself has no reason to make better product, because they are monopoly.
I don't think it's exactly this case at Apple, because the only monopoly I see at Apple is the fact they are probably the only mainstream tech company that is able to sell their products at almost any price they want (but of course it has some boundries).
But (!) right now it seems that the company is controlled by marketing people, because of that one thing: the obsession of making things thinner and thinner. I can't help myself, but the Apple product engineers seem to give up this fight with marketing people and that crazy Jony Ive. It really is an obsession without racional reason, because there are tons of things that could be improved, but clearly none of them sounds as good as the word "thinner". Jony should leave Apple, he was good when there was Jobs as the curator of his work. But right now he is lost in his autistic world (and I really know what autism means).
I'm really really curious how this all will turn out, but I think we have reached a point where the obsession is not just annoying, but it's really ruining the product. We haven't really seen Apple changing their opinion on their designs. My prediction is that between 2020-2025 will go through a recession until there will be pressure to change the lead / change the direction. They have like 2-3 years to really think about what they are doing before the average consumer will notice something is wrong. The tech people are noticing it for like the last 1.5 years, but the momentum is still there...