I'm struggling a little to understand what HEY does. They're suggesting that they have "reinvented Email" but is it just client side management that they've cha

I'm struggling a little to understand what HEY does. They're suggesting that they have "reinvented Email" but is it just client side management that they've changed? It sounds like they've brought spam management to the user, "reply later" which I'm not sure what the difference is between that and moving the email to a folder called "Reply Later". Maybe it's just that most users don't customise a personal workflow and this has interesting/sane ideas as defaults.