You never owe anyone anything, especially when they have laid out their “must read” criteria. As you said in another post, something to the effect of “who knows when life may end”, so why respond to others that do not matter and have basically told you, that your words do not matter?
What he said was basically human nature or there wouldn’t be millions of various top 10 best selling lists. Being #1, means you have value in most people’s eyes.
It very easy for me to decide if something will more than likely, be a waste or not. The title is big clue, if not, then their abstract, thesis statement or introductory paragraph should say it all. Then, if seems worthwhile, skim and scan, then know whether to read or ditch; simple :)