I order a lot of parcels online, and my inbox fills up with shipping confirmations, tracking numbers and delivery updates from many different couriers. A built-in "Deliveries" smart filter or label could automatically group these emails and surface the tracking number and expected delivery date in one place. That would save a lot of time compared with searching through the inbox every time a package goes missing. I explained why simple tracking tools matter in this lbc tracking post https://lbctrackingonline.org/ and I think Proton Mail could make following every delivery just as easy.