The median is not useless, but it has its flaws, just like the CPI has serious flaws.
The median is a 1-2 year lagging indicator. What they are saying, I think, is that the median’s downtrend is significant in that it will be reported widely in the news. Americans will finally understand and believe that home prices are falling. This realization ought to change buyer psychology even more, slowing down sales! Sellers will start lowering prices. Yes, the median is widely followed, so its numbers, for better or worse, impact the psychology of the market.