Psychological obsolescence might preclude the need for planned obsolescence (which is a very real thing, according to investigation by the Planet Money podcast episode #902 titled The Phoebus Cartel).
I recently entered a phase (gradual entry since like five years ago) where I'm attempting to buy things for longevity, rather than fast fashion, even if it means spending a prettier penny. I still have my Moose Brand bag, which I got for a steal years ago when they were a fledgling company. I'm still sticking with my North Face backpack from beginning of college, and most of my clothes too. Unfortunately I gave away a pair of beautiful and pricey Mephisto boots because they were giving me feet issues. Then I still have my leather Sperrys, which I got at a reduced price of $20 on Amazon that I wore for seasons at a time.
Basically, I have lots of items in great condition, but I recently caught the turn-of-season shopping bug and purchased Kork Ease sandals and a pair of Chacos. I told myself that I'd just live a life with fewer pairs of shoes: casual boat, athletic, formal, flats, flip-flops, snowboots, waterproof walking, and that's it. But I can't help but want ankle-height booties, cute leather sandals, functional ugly-cute Chacos. So even though my shoes are far from obsolete, I get the idea that psychological obsolescence is powerful and pervasive.