You might trust Windows and even actively want Recall and simply not want private Signal messages, specifically, to be captured by it. For the same reason that Recall already tries to exclude browsers in incognito mode, as mentioned by the article.
Yes, I can see why the feature would be valuable. But the blog post is an emotional rant against Recall. Signal is lacking a lot of valuable features, I doubt this is high on the list of most users, yet time and effort has been spent on it. If you don't want Recall, then don't use it.
