This is a popular opinion and there are tons of implementations of WYSIWYG text editors such as Typora and Obsidian that attempt to make their data model simple

This is a popular opinion and there are tons of implementations of WYSIWYG text editors such as Typora and Obsidian that attempt to make their data model simple like Markdown. But they all kind of suck, which shows that making that kind of editor is really hard.