They're not 'hacks' it's the people doing the redaction making beginner mistakes of not properly removing the selectable text under the redactions. They're either drawing black rectangles over the text or highlighting it black neither of which prevents the underlying text from being selected.
Keeping that secret would require sponaneous silence from everyone looking at these docs which is just not possible.
Impossible which is the point of the last sentence. Spontaneous secrecy when some people are discovering the bad redactions while publicly streaming is impossible.
Keeping that secret would require sponaneous silence from everyone looking at these docs which is just not possible.