I find anecdotes like yours bewildering, because I've been using Opus with Vue.js and it crushes everything I throw at it. The amount of corrections I need to make tend to be minimal, and mostly cosmetic.

The tasks I give it are not trivial either. Just yesterday I had it create a full-blown WYSIWYG editor for authoring the content we serve through our app. This is something that would have taken me two weeks, give or take. Opus looked at the content definitions on the server, queried the database for examples, then started writing code and finished it in ~15 minutes, and after another 15-20 minutes of further prompting for refinement, it was ready to ship.