I'm not very convinced. Yes the smartphone has eliminated the need for some of those devices, but there is now a rich market for accessories: Wireless charger

I'm not very convinced. Yes the smartphone has eliminated the need for some of those devices, but there is now a rich market for accessories: Wireless chargers, cables, battery backups, expensive phone cases, cheap phone cases, selfie sticks, phone lighting accessories, lenses. Plus smartphones create an entire economy of their own in terms of apps.