Even a decade of emails don't add up to very much storage unless you have lots of large attachments.
An average person's entire archive would likely easily fit on a small 64 microsd card. Which is like $10 bucks...
An average person's entire archive would likely easily fit on a small 64 microsd card. Which is like $10 bucks...
Also this is data at rest mostly that doesn't get accessed. Deleting it would save maybe a square millimetre of spinning rust somewhere but not meaningful amounts of power (that rust still has to spin)
The storage densities are constantly increasing to keep costs low. SMR drives have significantly pushed up the achievable densities at the cost of write performance which matters little for cold data. The 1PB/node mark was breached a few years ago.
Few players have the budget to store these volumes of data on flash, especially since you're always erasure coding for redundancy which adds anywhere from 50-100% storage overhead, depending on other tradeoffs.
HDDs are a remarkable invention and not going anywhere soon. Heck, I think tapes aren't dead either.