I just tested it on my instance. You can create a public share by setting the mode to “Write”, which is accessible without logging in as a user (but with optional password).
It works, but one does not see any files, not even the ones you uploaded yourself. So for example if you updated the file and need to re-upload it, there is no way for you to delete the previous one.
You can also create a shared “virtual folder” that is seen by multiple users, and then you have fine grained control on a user basis (Users > burgermenu > edit > ACLs > Per directory permissions) there you can mix and match from a list of ~15 permissions. To upload anything to that virtual folder, you’ll have to properly log in as a user.
Hope either one of the ways works for you. Cheers
Battleforge is another good example. It took about 10 years for the community to reverse engineer the server and host their revived version. https://www.skylords.eu/