You might read my own current opinion about binary variables here. In short, it is not a sin to use binary vars with PCA if you use the analysis simply as variable-reduction technique - for example, for plotting purpose, - without attempting to interpret the components as latent features. If you go as far as to interpret you should better use factor analysis in proper sense, not PCA; and then binary variables posit a problem since factor analysis assumes contunuous variables, what binary variables are clearly not.

You might read my own current opinion about binary variables here. In short, it is not a sin to use binary vars with PCA if you use the analysis simply as variable-reduction technique - for example, for plotting purpose, - without attempting to interpret the components as latent features. If you go as far as to interpret you should better use factor analysis in proper sense, not PCA; and then binary variables posit a problem since factor analysis assumes contunuous variables, what binary variables are clearly not.