The amount of memory in a device is completely irrelevant if the user's task at hand has its needs met. Would I like more RAM? Sure, spec wars to fight, memory is realistically very cheap, etc, but it's not going to stop me from upgrading if we only find 1GB of RAM today. That said, I also upgrade to every new iPhone release -- sell the old, buy the new, and only have to absorb the cost of the difference.
Developers are obviously able to push the bounds as-is (most iOS apps look/function similarly-to-or-better than Android versions of those apps on higher memory handsets).
You also have to factor that iOS's multitasking doesn't keep things in volatile memory forever, so that 1GB goes a long, long way with how lightweight most of iOS is out of the box. When you're able to develop for a fairly static/specific platform, and have new APIs like Metal, you're able to eek out every last bit of resources and performance as needed.
The only current drawback I can think of to maintaining 1GB of RAM is --
Safari tab refreshing -- more memory would help this, but that's also a bandaid, it doesn't solve the underlying problem of the browser taking more memory than many other types of apps. Still, for those using lots of tabs at the same time, no doubt this limitation is a concern.
That's not really my use case (I use 2 tabs at most typically, and if I do use more, I don't mind the refreshing), but I do understand, different strokes for different folks and all.