If it helps I believe the EU just made it illegal two days ago to release updates that make battery life worse. But I could've confused some of the details there.
They just implemented iOS 7 with much more compute requirements, so only newer phones were able to run it smoothly. The progress of mobile CPUs these old days was crazy, so I don't really complain about it, it was inevitable.
It seems like A would have been whistleblown by now, and B would be idiotic for them to do on purpose since it would make their new devices unnecessarily slow too.
My opinion is basically B but without malice, it's just that they're obsessed with tons of animation and other eye candy, and added a lot of bloat in those years in general, rushing code out the door out of a desire to hit iOS release dates and the synchronized iPhone release dates they used to have.
Yes, they did in fact prove that. That's why Apple had to pay $500 million dollars to settle, because they got caught doing shady shit.
It was still the correct course of action, and obviously not done maliciously -- a phone that was so slow it was annoying to use, and a phone that reboots 10x a day are equally 'incentive' to buy a new phone, so I fail to see how the throttling benefited Apple one bit.
In fact, I'd say the unreliable rebooting one would have provided stronger incentive to replace it vs. a slow one.