[londons_explore]

To my knowledge gmail has never purged unused accounts.

It would be a security nightmare to let anyone else register and reuse an email address anyway. So the only benefit is saving a little disk space.

But disk space for highly compressible text that will probably never be accessed is super cheap.

[londons_explore]

If costs got too much, they could easily take all very old emails and archive them - for example onto tape and cut down to one or even no online replicas.

Then add a button that says "Some emails and attachments older than 1 year are archived. Click here to retrieve them (takes 24 hours)"