Obviously needs are different. On tour I rarely ride in the dark, but have a small rear light and a "miners headlamp" (which doubles as both front lamp and torch in camp). Batteries for LED lamps last for ages with such little use.
Finding outlets to recharge iphone has never been a big problem, especially if staying at campsites. OTOH going without iphone for a few days is no big deal for me.

In the also somewhat unlikely event of hub failure, I imagine finding a replacement and rebuilding a wheel would be more problematic, especially in some parts of the world.

So - for me - the cost and weight isn't justified.

However, if you wild camp a lot, are more dependant on bicycle lighting, GPS, google maps etc, then I can understand the need of a dynohub.