I am frankly astonished at the number of otherwise-intelligent people who actually seem to believe in this stuff.

One of the worst possible things to do in a competitive market is to trade by some publicly-available formulaic strategy. It’s like announcing your rock-paper-scissors move to your opponent in advance.

Technical analysis is a basket of heuristics. Support / resistance / breakout (especially around whole numbers) seems to reflect persistent behavior rooted in human psychology. Look at the heavy buying at the $30 mark here, putting a floor under silver: https://finviz.com/futures_charts.ashx?p=d&t=SI This is a common pattern it can be useful to know.

A couple of subtleties in that. Rather than rock paper scissors with three options, there are hundreds of technical strategies out there so you may still be doing something unusual. Secondly the mass of the public are kind of following a technical strategy of just buy index funds because the index has gone up the past. Which is ignoring the fundamental issue of whether stocks decent value for money at the moment.