The source for the HTML page points to inst/images/logo.png, but the current version of index.html in the gh-pages branch shows a link to assets/images/logo.png.
The assets folder doesn't exist in the gh-pages branch.
I'm not sure if this requires a change in the pkgdown GitHub Action, or some other variation in pkgdown::build_site() so that the assets folder gets correctly copied/created?
Perhaps usethis::use_logo() might be of use to help solve this.