While the app optimization may have played a small part, I know for a fact that when I updated my iPhone 6 to IOS 11 it basically became unusable until a whole

While the app optimization may have played a small part, I know for a fact that when I updated my iPhone 6 to IOS 11 it basically became unusable until a whole year later when they released IOS 12. I upgraded to the 8 during this time and really regretted it once the 6 was updated to fix all the issues. If I had been able to downgrade my software it wouldn't have been an issue, but Apple forced my hand to buy a new phone by breaking my old one with zero recourse available to me. I'm now very, very careful to not update software on my phone until I've vetted it carefully. Apple lost a lot of goodwill from me with that whole shitshow.