I get why tracks are not available to a Nano from iCloud or downloaded to MAC, but what then is the point of Match?

As mentioned, if you are using the Apple Music service, it DRM protects any matched tracks so they cannot be synced to the iPod Nano. You should get an error if this is happening that reads something like : "Some of the items in the library were not copied to the iPod because Apple Music songs cannot be copied to and iPod".

Not sure why you are using both subscription services. Apple Music and iTunes Match do essentially the same thing. Paying for both is pointless.

Not even sure you can use both at the same time in the Mac's Music App, would not know how that would even work. Not even sure how you could separate the tracks from each service.

But again, as mentioned, the tracks downloaded from the Apple Music subscription service are DRM protected and cannot be transferred to an iPod (iPod Touch excluded) in any way.

If you are indeed subscribed to both services, make sure you actually are, then consider cancelling one.

Also, make absolutely sure, the tracks on your computer are not the DRM protected ones from Apple Music, but your normal unprotected tracks.

You should always have a local non protected copy of the music in your library.

Your question is a bit confusing.

iTunes Match is completely separate to an iPod Nano, its not meant to work with it at all. It has no ties, relation or impact to how the iPod Nano gets its music at all.

iTunes Match allows internet capable devices signed into to your Apple ID to access any music that was matched or uploaded to the service over the internet.

The iPod Nano does not connect to the internet, nor can it access iTunes Match in any way whatsoever.

The iPod Nano gets its music from the computer it is synced with, the same computer that should have that same iTunes Music library that was synced to iCloud through the iTunes Match service.

The computer that holds your library can sync the songs to the iPod Nano regardless of the iTunes Match existence.

Any music downloaded from the iTunes Match service to the iTunes application or the Music App on a Mac will then be able to be transferred to the iPod Nano via a regular sync.

iTunes Match does not DRM protects your tracks and once downloaded can be used with an iPod Nano.

If you are using the Apple Music subscription instead of iTunes Match (different and separate subscription services), then music downloaded from there is DRM protected, and would not be transferable to the iPod Nano, but should not really matter, if the computer you sync the iPod Nano with still holds your original and unprotected tracks and albums.