This is admittedly a bit pedantic but it’s not that the risk doesn’t exist (there may be quite a lot to gain from having your info). It’s because the risk is quite low and the benefit is worth the favorable gamble. Not dissimilar to discussing deeply personal health details with medical professionals. Help begins with trust.
There’s an implicit trust (and often an explicit and enforceable legal agreement in professional contexts (trust, but verify)) between sys admins and troubleshooters. Good admins want quiet happy systems and good devs want to squash bugs. If the dev also dons a black hat occasionally they’d be idiotic to shit where they eat. Not many idiots are part of teams that build things lots of people use.
edit: ope replied to the wrong comment
The right thing to do is offer a program to replace the battery. Even more right would be not designing anti-repairability into your products. 🙊
Throttling the processor to extend the life of the phone is a reasonable temporary alternative IF it’s transparent and opt-in. Effectively forcibly downgrading the hardware spec of a device I own without even telling me is a serious breach of trust at the very least, no?
I agree the decision may have resulted in less e-waste but, even if so (and assuming all is well-intended), that can’t justify hijacking consumer’s belongings. That’s a dangerous precedent to set.