The overload of the word “tags” in org-roam is problematic, in my opinion.
We have org-mode tags, applied to a heading or as #+FILETAGS; the - tags :: links in org-roam; and the roam tags in org-roam, defined as #+ROAM_TAGS or implicitly by the directory.
The behaviours diverge and it risks being very confusing as the documentation expands.
I’d be careful to separate the terms clearly by using systematically the same name, such as: “org tags”, “roam tags” and “roam links”.
I would even suggest that the - tags :: convention be replaced by - links ::.
In my case, I do no use roam tags as a replacement for roam links. I assign them very different semantics.
Roam links target other notes, i.e. other units of knowledge. Yes, they can start out as empty notes, but sooner or later I find that there’s something I want to write in them directly, or copy over from my fleeting notes.
Roam tags I treat as metadata: they denote the type of the note (project, meeting, person) and how it should be handled by the system. The way the system is designed, I think you will find roam tags to be very impractical if you start using them as links to other units of knowledge. They’re used much more sparsely than links.
I believe that if you start using roam tags as you would use roam links to empty notes, you’ll quickly bump into the limitations of the search interface. I have an Evernote database with several hundred tags and if it wasn’t for the fact that you can organize them hierarchically and with a query language, they’d be totally useless.
In summary: each one will find their way to use these things; but it would be very important to name them consistently so that we can understand each other, especially for newbies reading the docs.