Are older iPhones being deliberately slowed?

The chart below shows iPhone 5s GPU performance over time. Each bar shows the average 3DMark Sling Shot Extreme Graphics test score calculated from all results submitted during that month.

A higher score indicated better performance. The bars are coloured according to iOS version.As you can see, iPhone 5s GPU performance has remained consistent from iOS 9 to iOS 11 with only minor variations that fall well within normal levels.

The next chart below shows CPU performance over time as measured by the 3DMark Sling Shot Extreme Physics test. Again, it is clear that iOS updates have not had a significant effect on performance.

The charts for the iPhone 6, iPhone 6s, and iPhone 7 tell a similar story. GPU performance has remained consistent across iOS versions with only minor variations.

The graphs for CPU performance show a very slight drop in performance over time - possibly due to minor iOS updates or other factors - but a user would be unlikely to notice this small difference in everyday use.
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