What are the algorithms used for encryption? What are the defaults, do they now match the currently best known approaches? Also why can't I use the application

What are the algorithms used for encryption? What are the defaults, do they now match the currently best known approaches? Also why can't I use the application to do symmetric encryption? Namely the problem with GPG is that its defaults are still ancient (maybefor compatibility with whatever, I don't remember the excuse) and to reach the currently best settings one has to jump many, many hoops, even for simple task of symmetric encryption.