Can anybody explain this Bootcamp Disk Utility disk/container/partition hierarchy, please?

Looks like you somehow renamed your macOS Data volume as "Windows Air". You should rename the volume using Disk Utility so it matches the name of your other macOS system volume...just make sure to add " - Data" to the end of the name so it clearly shows as different from the main system volume. I believe Monterey still had that naming convention. Unfortunately Apple makes this so confusing & difficult.

For example, the original factory configuration would have the following layout:

Apple SSD

Container disk1

Macintosh HD

Macintosh HD - Data

I'm only showing the parts you have expanded in your screenshot.

Link below on setting up Bootcamp for windows 10

Install Windows 10 on your Mac with Boot Camp Assistant - Apple Support (CA)

Link below on Removing a Partition created by Bootcamp and is the only sure way to get it right.

Doing otherwise may require Reformatting the Entire Drive to gain back the Unused / Unallocated space.

Remove Windows from your Mac using Boot Camp - Apple Support (CA)

I'm not very familiar with BOOTCAMP, but I'm pretty sure it is installed in a partition (which is called a Container on APFS). You don't have a second container. You just have an APFS Volume. A Volume is more of a virtual separation but behaves like a disk. Volumes share the storage space allocated to the Container.

The Windows Air volume at the bottom is the extra bit in your setup. I don't believe it is possible to convert a container to a volume, so I don't know what happened to your BOOTCAMP partition.

You can set a quota on a volume, and perhaps they figured out how to run it from a volume instead of a container. The instructions still reference making a partition and I remember it being a partition. I don’t have a Mac that can use BOOTCAMP, so I can’t check.

I don't use BootCamp, but from what I've seen posted on these forums...the "Windows Air" entry within the Container seems wrong. Usually BootCamp creates a separate partition by splitting the Container. The "Windows Air" item at the very bottom seems to be the correct item and represents a separate partition.

I don't know why you have a "Windows Air" volume within the macOS Container...doesn't make sense unless it is some new Bootcamp feature perhaps for shared storage between macOS & Windows? I have seen Disk Utility report all sorts of weird layouts even just for a simple macOS installation where the entries will be duplicated or even out of order.

Your best option is to perform a clean install of macOS by erasing the whole physical SSD (Intel Macs only) and starting over. People really should do this whenever they acquire a used computer since who knows what the previous owner has done to the drive layout or even macOS itself.

P. Phillips wrote:

IMHO the solution to getting it back to “Normal “ in the shortest amount of time is a compete Reformat of the the Entire Drive.

It would remove any Partitions and Start a fresh

Definitely agree especially if a clean install was not performed after acquiring the used computer. If a clean install was previously performed, then my later suggestion to rename the "Data" volume should be sufficient.

Seems we were writing our posts at the same time.

Much like the above poster - MS Windows on macOS - not my cup of tea.

I just know how it should work and what to do when it does not

IMHO the solution to getting it back to “Normal “ in the shortest amount of time is a compete Reformat of the the Entire Drive.

It would remove any Partitions and Start a fresh

Agree on all your above points .