Sure it does. Author could've been clearer about the goals, though. Say that rather than pre-selecting 50 stocks, we ran the analysis on the whole market - then each component intuitively corresponds to some segment of the market. For example, some component might correspond to agro companies whose prices fluctuate with the weather. Another component might correspond to NFLX and other companies who rely on AWS, which fluctuate together based on cloud storage price changes.
This kind of interpretation kind of falls out of the math (the eigendecomposition/SVD/covariance matrix interpretation of PCA in particular).
This kind of interpretation kind of falls out of the math (the eigendecomposition/SVD/covariance matrix interpretation of PCA in particular).