I want to allow other iMac's on my network to be able to put stuff in my Dropbox folders

dropbox is in the cloud on the internet your network have no bearing when it comes to other users having access

How to create a Dropbox file request - Dropbox Help

Solved: How do I allow others to upload files? | Dropbox Community (dropboxforum.com)

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dropbox allow guest to write - Google-

It's Dropbox vs Drop Box: two different things.

Dropbox - cloud storage

Drop Box - a folder for receiving files from other local users and users on the same network. Can be found in your ~/Public folder.

you mix things to gether

dropbox offer you storage in their cloud

if you install the dropbox app on your computer you can set it to sync with a dir on your local computer

sharing the dir which also happen to be sync'ing to dropboxs server is no different than sharing any other dir

it would be transparent to whatever accessed the shared folder that it also synced with a cloud solution

try reading

Set up file sharing on Mac – Apple Support (UK)

How to share a folder to your network in MacOS | ZDNET

more macos share dir to network with write access to guest account - Google-

Hello!

In trying to understand the question, it seems like you are trying to change the permission for your home folder to be Write Only, something that should not be done.

You may have already done this, and I might've misunderstood the question, however, to set up file sharing on a Mac system, you would do so through your System Preferences/System Settings, depending on the version of operating system you're running you would navigate to sharing and you would activate file sharing.

On most systems, the public folders of the local accounts will automatically be shared, giving network users access to the dropbox folder inside. This can be modified so that the only folder you share on the network is your users dropbox folder. The permissions for accessing that dropbox folder are also automatically set to write only and can be verified on the screen when you are there.

Hope this helps!

If you were to create a new folder and share it, could mac computers on your network write to it? If the Drop Box folder is truly the problem, any folder can be assigned the "Write Only" permission and turned into a Drop Box style folder. This is not answering your question as to why your setup isn't working... just trying to see if a workaround works. and if it does, that might lead others to the solution you are looking for.

Ok. Let's test to see if it is something wrong specifically with the computer. Can you go the opposite direction? Can you access the Drop Box folder on another Mac from this problem one and write to it?

Try this: under users and groups select "allow guest users to connect to shared folders"

Yes, there is a write only "$HOME/Public/Drop Box" folder on the Mac.

What I am unsure of, is whether or not the SMB protocol can properly pass the write only permissions across the network. The SMB protocol was written by Microsoft, and not Apple.

Now when Apple was using AFP (Apple File Sharing) protocols, they DID correctly pass the write only permissions between systems.

NOTE: I really do not know if this is an SMB issue or if it is something else. I have not studied the SMB protocol. And it has been years (like since 1995) when I was busy studying AFP for the PATHWORKS for OpenVMS project.

Did you give macOS Terminal "Full Disk Access"?

In Monterey, I think this is somewhere under System Preferences -> Security & Privacy.