Maybe "a competitive labor market" doesn't, but "job hopping" does. That is, in fact, the definitional meaning of job hopping. They specifically made the claim about "job hopping" as pertains to a mechanism for achieving wages. This is incompatible with finding an optimal fit -- even if you found your optimal fit, you would essentially be taking a massive wage cut to stay at your optimal fit job for more than a couple of years, if job hopping is the chosen mechanism for society-wide wage growth. I was responding to the claim that was made about job hopping, not some other claim about competitive labor markets.