I think the idea is that there will be cluster mailboxes in more and more neighborhoods. I live in a development that just opened two years ago and that’s what we have — 60 or so boxes on every other corner. Speeds up delivery considerably.
That’s exactly what they’re planning; they started doing in in new subdivisions back in the 1980s. For parcels it’s an improvement, because each cluster has a few large lockers- the place the parcel in the locker and put the key in the recipient’s mailbox. Saves a trip to the post office.