I classify this sort of thing as Vanilla Design. It’s not as bland or as fast-fashion-y as consumer, not as overwrought as most design for semi/full technical audiences is, and it’s not the same as what’s usually thought of as opinionated design. It’s vanilla: expected, flavourful, normalised and high utility.
Prestructured WYSIWYG solves both problems. You get the expressiveness of abstract semantic styles like bold, italics, and monospace, and you get larger sizes for headings. But you avoid both the “missing font” technical problems and the “terrible font” design choices. If you use Apple Notes or Messages, you better like Apple’s San Francisco system font family, because that’s what you’re going to get. It’s great for accessibility, because all the type sizes are relative, not absolute. And these preset styles largely map well to Markdown, which itself has no concern with font choices or specific text sizes.