You are saying that every single house that was sold after the crash of 2008 was a shithole? I don't believe that.
And even if every single place was a shithole, the land, a certain neighborhood and the house after a renovation would still have made it a good investment.
Let me clarify: inner-city homes, where most of the people that argue with me base their "real estate can never go down" arguments. I have read online several times about unrepentant city councils that keep property/land values high, despite their unworthiness and high crime rates in the area. Take Detroit. Take Baltimore. We're talking about more than just single renovations needed, but entire neighborhoods.
If you can buy a well-kept house after the Crash, my hat is off to you. But the odds are against more than a handful of success stories.