Why was the warning to add content description to image views and image button removed in AppCompat

When building layouts in android, if you use an ImageView or an ImageButton without adding a content description, then you would get a warning telling you to add a content description to the views with AppCompatImageView and AppCompatImageButton that warning is no longer available. I thought this is because the implementation for AppCompatImageView has a default content description based on the content of the view but talk back still reads it as an "un labelled button", why was the warning removed?

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