It may be worth noting that the Nexus 5 came out more than two years after the iPhone 4S (Oct 31, 2013 vs Oct 14, 2011), and as of now it hasn't even been 2 years since the Nexus 5 was released.

That said, it has been less than 4 years since the iPhone 4S was released; they shouldn't be failing yet, and that reflects poorly on the iPhone (as well as iOS) in your case. However, I'm also not yet convinced that the Nexus 5 will be operating well in late 2017 - that's yet to be determined.