But you are not going to convince me Apple has conspired to slow devices down for the only reason to increase sales.
You cant disprove planned obsolescence because the argument you are using to dismiss the YouTube videos applies to your own evidence (benchmarks) in spades as they both can be manipulated and one of them can be manipulated by the company itself. We are at an impasse. There is absolutely no way for you to convince me planned obsolescence does not exist unless you can explain why my iPad Mini was wrecked my Apple on iOS 9 and why my iPhone 6 runs at half speed on iOS 11.
In the meantime, these threads will continue to pop up after every iOS release until Apple fixes the issue once and for all.