For example, the comment mentions that the the "Median Sale prices for new houses sold" is in dollars. Yes, he is correct. But looking up an inflation adjusted median price gives the same result, that house are more expensive than before. So yes, he is right that the graph can be technically misleading, but the point of "WTF Happened in 1971" still stands.
I think there are many midcurve takes, where one would argue how 1971 is wrong, but isn't it the case, in reality - that housing, college, wage, etc. have all been doing worse for a few decades now.