It's one reason to pursue 'smaller' opportunities with lower variance of return expectations but higher median returns -- for example many niche businesses -- than industries with gigantic return expectations. The latter attracts far more entrants, and while somebody gets rich, the median player does not. But this isn't clear to new entrants because of survivorship bias.
Somewhat related to this is the data availability bias. Big opportunities tend to have much better data sets, and so are easier to study and receive more attention. Many niche industries are closely private and are smaller, so do not have much publicly available data, making study difficult and attracting less attention. Therefore like moths to light bigger industries receive more study and more entrants even though their median expected economics are worse.