I do think tech undervalues experience and overvalues familiarity with technological fads. That said, there are two sides to the coin. Those other fields the author mentions all aggressively put people into "tracks" early in their careers.
Take the corporate lawyer, for example. His job is secure because most of the competition for his job from his cohort was tracked-out in earlier filtering stages. If tech was like law, you'd have job ads for people with 10+ years' experience saying "top undergraduate school (MIT/CMU/Stanford/Caltech or the equivalent) and top company (Apple/Google/Facebook or the equivalent) required." That would certainly create a lot of insulation for people who went to MIT, interned at Google, then put in 3-5 years after graduation to earn a credential they could bank on the rest of their careers. I'm not sure we'd all prefer that to be the case.