My research is on specific publications and their publishers. Should I include all articles mentioned in the bibliography? My dissertation is on magazine publishers. My primary source material includes magazines.
My query is, should I include all the articles mentioned in the bibliography? Or only those that I consider the main articles? Or only the magazine itself with the range of years that are included in the research?
The individual articles have all been referenced  in in the notes.
In the style guide it says: if an article is cited in the notes, then it can be omitted in the bibliography. One can include an article in the bibliography only if it’s central to an argument being made.
This does not really address my query, as central to the argument is the publication itself rather than individual articles. (As the response from my supervisors is not definitive  I'm asking for other valued opinion, thanks.)
Generally speaking
If you are referring to particular content of particular issues, you should cite them.
If you have a database of the contents of the magazines and you work with that, then ideally you publish the database, or in any case explain how you created the database and what was included. In that case you would cite the database, if published, or otherwise refer to it, but you would not cite specific articles unless you use their particular contents, as per the first paragraph.
What are the notes?
In your question you mention that individual articles have been referenced in the notes. Are these notes a part of the dissertation or something distinct?
If you dissertation is a collection of articles and these notes are the articles, for example, then you are presumably writing an introduction that ties them together. Then the introduction would cite whatever it mentions, but likely not very many individual magazine articles, as the details would be left to the research publications.
If you mean some kind of notes you have written for yourself and not to be published in any way, then they don't matter for the question of what to cite in the dissertation itself. The dissertation should stand by itself, without needing private information.