It's a really approachable theory and contrary to what you'll read in tech message boards - doesn't remotely boil down to "the market can't be wrong". Burton Malkiel (economist most famous for writing "A Random Walk Down Wall St" and being a longtime advisor of Vanguard) has a paper talking about the early 2000's pushback.
It gives a good summation / spells out some critiques / offers his reasons for disagreeing:
