Good assessment.

Apple, in large part, is a luxury brand. Their biggest and most important advertisement is their users - people who want and can afford a glamorous, high end lifestyle, and their acolytes. So these are the people Apple caters to. If your phone is more than a year or two out of date, you are no longer a customer who functions to represent the luxury Apple brand - you are just a follower, who contributes insignificantly to the company's revenue stream. So keeping parts on hand to repair your phone, and employees trained to do the repair, is money down the drain.