The technology has been demonstrated to work but it seems to be taking quite a long time to make it into consumer devices.
If I can waste the charge of my new Android phone in a day or, alternatively, optimize my usage and phone configuration and get two days of batterly life, that means I'm still part of the power equation. If, instead, I have to choose between usage patterns that give 8 or 9 days of power, respectively, I will certainly not give a damn.
Battery life is a perfect example of "good enough". Would it hurt so much to equip the phones with larger batteries instead of, say, 1500mAh that seems typical now. As for the latest smartphones, it can certainly not be because of the physical size.