The important bit is line 9, “gio-fam-backend”. The line 12 explains the package is no longer required due to being obsolete.
Doing the following (seems) to fix it (during my issues with glib20 and rubygem-facter)
Line one is recompiling ports which depend on gio-fam-backend
Line two is deleting the gio-fam-backend port
Line three is checking all ports and updating as necessary