Well they didn't, because "[...] to drive customer upgrades" is the key part they state they are not doing.
> lied so blatantly about planned obsolescence.
Again, they didn't, they aren't admitting to 'planned obsolescence', only attempting to prevent shutdowns.
When you write an entire article explicitly stating that you made your older products slower compared to newer ones, and then at the end you offer a promotion on batteries, you kind of are trying to "drive costumer upgrades".
On planned obsolescence: of course they won't admit it. But at the end of the day, they made old iphones slower, and new iphones faster. On purpose. How is this not planned obsolescence?
If the change had simply made all iPhones 6 and 6S throttle down CPU 20% then replacing the battery wouldn't 'fix' anything. That would certainly be planned obsolescence.
What they said "[wouldn't] degrade the user experience to drive customer upgrades"
What they did "degrade the user experience"
I can't think of any reason they would do that in good faith instead of simply telling users that their battery is old, this is why your phone is shutting down, please replace it.