Whoa, this thread has been a trip. A lot of high emotions coupled with misinformation in a feedback loop. The statement Apple published clarified their first statement about throttling, acknowledging that the safeguards put in place to prevent a random shutdown were kicking in when they weren't supposed to in some cases.
The random shutdowns were the priority to fix, but as time passed, the safeguards were affecting other phones with slowdowns when they're not supposed to and Apple is investigating a fix.
To get angry at Apple for slowing your phone when they were really trying to help it is silly. Either you choose to believe Apple, or you don't, but have a little empathy that this problem may not be so easy to fix and Apple has made a very public statement that they're working to address the issue. One of those options is the reduced price battery replacement while they work on another fix.
This may very well lead to another quality program—one of dozens Apple has done across all of its products over the years. Get angry at Apple and buy into the forced obsolescence paradigm, but what other company for general consumers goes out of its way to support older products 4, 5, 6 years after the fact?
There was another claim that Apple has been doing this for "years," as in purposely slowing down older devices, yet there's been no evidence presented. This is another silly thing to get worked up over because there are so many factors at play. Old electronics getting slower with age is not unique to Apple. My old undergrad Lenovo still running XP runs like crap, but that's really in comparison to my specced out 2016 MBP.
It's been said that there is probably a design flaw in the 6 and 6s series of phones. Are you really going to get angry that Apple isn't perfect and might have messed up with the design, and view their attempts to address it as deceptive? The iOS update that introduced this management did note these changes. Then as batteries got older, these changes started doing something they shouldn't. Apple stated their reasoning why they thought this was to be expected, so again, you can either believe them or you don't.
And whether something would have happened if Apple didn't get "caught," we'll never know now. You'll have to choose what to believe. But with a company that goes out of its way to provide this level of extended support to the general public, I choose to still have faith that Apple will continue to try to make things right.