Some interesting points there. I think Royal Mail are good at the small parcel delivery and ideally they would have a large enough market share to be able to do this daily - it's the low value letters that are going to cause them problems.
My 85 year old Dad still receives more than one item of normal mail most days, whereas i get maybe about one thing per week... I would guess most people are somewhere in between...
Re small parcels - my late partner received something she'd ordered literally almost every day through RM, mostly small things like jewellery or dog collars or something.
If that is anything to go by, i would think postmen are still covering pretty much all the ground every day anyway, so might aswell continue with daily letters aswell.
However, remembering, atleast round here anyway, they each drive out in their own van now, presumably because of all the parcels and also doing the collections, perhaps letters and small parcels could be split, with the parcels/collection duties merged with neighbouring rounds thus reducing the number of vans out, and letters rounds going back to posties totally on foot again, with the possibility of covering each street just every other day, thus reducing the number of said staff. Not necessarily advocating this, just suggesting...
I do wish, while things are the way they are atleast, that the large barrows could be used instead of a van for every round - one thing which has stopped me going back to that job, as i don't drive...
By the way, when i was a postman thirty years ago, we had "overweight" drivers, each one covering maybe about fifteen or twenty rounds, who took items too big or heavy for us to carry in our bags, and also second bags to drop with us if there was too much for one bag. We'd normally have about three or four small parcels ("packets") in our bags, plus about a couple given to the driver.
Yes, as
@judethegreat says, the vast majority of post boxes are now cleared as part of the delivery rounds. The "last collection" being shown as 9 am is simply a convenience for RM as it saves them having to set a specific time for each box based on the usual timing of deliveries around it. For example, there's a 9 am one down the street from me that's more like 10.30 am in reality because that's the usual time they're doing deliveries in the street.
Thanks. Not setting a time also means the postman has flexibility, aswell as being cover for if the round is covered by a relief who may not know it so well and take longer, or is doing it after having done their own round that day.
EDIT - Just remembered another major difference from thirty years ago - we had two deliveries per day then, so another reason why they each come out in vans now as it is all combined in one delivery..