Well, I don’t know if it should work or not. But to help you in your diagnosis/search, the context (as I understand) is this: Vim bindings are supplied through the CodeMirror project: CodeMirror: Vim bindings demo
And here you can find open issues regarding Vim in CodeMirror: Issues · codemirror/codemirror5 · GitHub
Before recently, there was no maintainer for this project. And Vim bindings in CodeMirror was only a small subset of the full features of Vim. (It is not an actual Vim implementation). And as far as I have understood, because of the popularity of Obsidian, there is now activity on this project again.
And we also temporarily lost Vim bindings support when the devs upgraded to CodeMirror 6. But there was a bounty and now it is being worked on again. I have no idea if there is any feature disparity between CM5 and CM6 yet.