I endorse this analysis.Many classical chart patterns worked well in the 1970s and 1980s due to the high serial correlation. The shape of the patterns was mostly irrelevant although some behaved better than others due to their duration. The key behind their performance was that there was high probability that up days would be followed by up days and down days by down days. As a result, a double top or a head and shoulders worked as long as they were confirmed. But that is not the case any longer and false breakouts prevail. Thus, chartists of the 1970s and 1980s were fooled by high serial correlation. When the serial correctional became negative, charting along with most indicators stopped working. The market was ruthless in that respect and took the money of naive technical traders. Some still struggle with such methods, not doing their homework. Some others hope that serial correlation will return to the markets before they are too old to trade. I hope it will because there should be some form of wealth redistribution among traders. But the situation is much more complicated and instead of a return to high serial correlation we may see something else.
This also means that if you can find assets with high serial correlation, traditional tech analysis should work well. I normally use tools like the TSI to find assets of this variety.
(and it works in the opposite function too, low TSI score assets have low/negative serial correlation and generally make for good mean reversion trades).