You forgot to tack on the rise in prices of SSDs too, so that's $50 per year at least.

>Most adults I know now use their phone for everything

You mean the cloud for everything. A lot of phone tasks share their computational and storage workloads off in the invisible ether that has actual computers with real costs behind them. Amazon has no problem with bumping up their costs in order to pay for their fleet of servers. I mean, what business doesn't use the cloud these days.