I think the very name Rich Text Format suggests to users that formatting is central to Scrivener’s offer, and that pretty much equates as being akin to WYSIWYG for them, irrespective of what the manual or forum or website might say.
I do some work with creative writers who are struggling to write. Most are suffering from Word-constipation: they have got into the habit of opening Word and being overwhelmed by the formatting (not necessarily WYSIWYG) goodies available to them. It’s all just noise and digression. First thing I do is to break them away from Word by getting them just to write on paper or a board or a wall or window … literally anything that allows them just to write. Even then, people will add some formatting to their words: underlines, block-caps, etc. (They default to a kind of Markdown.)
When (or if) we get back to using a computer, we start with a plain-text editor or something clean, like iA Writer or Bear. For many, Word, word processors, RTF, etc are a curse. They are tools really designed for typists (back in the day) or people doing clerical work. They have nothing to do with the art and skill of writing. And professional pre-publication formatting should be done with a specific tool.
I think most (creative) writers need a clutter-free space to write and another space to understand and manipulate structure: the editor and the binder in Scrivener.
From my experience, the pared-back interface of iOS Scrivener is a pretty ideal writing environment (would be nice if plain text were an option or the default), so a version of that running on a Mac would be a joy. If there were an optional companion tool that added in more Mac-specific goodies, at least the people who want all the extras would still be able to have them. But, from what I have seen of creative writers working with professional publishers, I doubt many would need such an extra tool.
Write. Structure. Edit. Compile. All in Scrivener.
Design and format and typeset elsewhere.
And with only one developer working on Apple versions of Scrivener, wouldn’t it help workloads and enchantments to have a universal app with one core development stream that can satisfy most (I assume) users? And isn’t Apple with its new silicon and promotion of iDevices making the market ever stronger for universal apps?
Think two apps that work differently across devices just adds to user confusion. A single experience has got to be more useful for the majority, hasn’t it? And if Apple is heading that way, isn’t “the old way” of having two different apps just going to lead to Scrivener losing users as time and progress march on?
I completely love Scrivener (save for Dropbox), but it definitely overwhelms many people with its RTF / quasi-WYSIWYG formatting, its huge array of options, and its different versions.