Which is the point of the article. This is something that should be available to web apps, but there's no motivation from Apple/Google to make that happen lest

Which is the point of the article. This is something that should be available to web apps, but there's no motivation from Apple/Google to make that happen lest they tank their app store profits. Password managers provide a means of autofill with FaceID, which is the next best thing. This is how I log in to most native apps too.