This was always blown way out of proportion and taken out of context.
Basically all mobile devices use lithium ion batteries. After a certain number of charge/discharge cycles, these batteries are degraded, and cannot hold as much power , and/or provide enough for certain peak power demands from the soc.
If your phones battery was degraded sufficiently, the phone might have shut off if the battery couldn’t provide enough power during a ‘surge’ or peak demand during heavy use.
This would for obvious reasons be a really annoying user experience and people would complain.
They would also probably look to buy a new phone if their old one kept shutting off. Makes sense. Well, Apple decided they could throttle the speed of the soc to limit those peak power demands on the degraded battery, but only if you had a degraded battery.
This allowed people to keep using their old phone instead of needing to buy a new one. The only problem was Apple did a terrible job explaining this to the public.
People are convinced that Apple “slowed the phones down as part of planned obsolescence”, like some conspiracy to push us to buy new phones.
That was always a nonsense argument, because throttling phones that had batteries that were degraded actually let people use the phones longer, before needing to either replace the battery or upgrade the device.
Anyone without an agenda could understand this clearly, but as it goes on the internet, misinformation ruled the roost and people think it’s some malicious conspiracy.
Notwithstanding Apples history of supporting these devices for years longer than their competitors in terms of software and OS support…
Anyway, the topic always irked me because people were claiming the opposite of what was true, and were stubborn and unwilling to learn that they were misinformed.
The settlement Apple paid over the matter was about how they basically did not explain this transparently to their customers, not that they throttled the frequency of the SOC on devices with degraded batteries so they could be used longer without annoying shutdowns.
Ugh.