I experienced the same thing (had previously uninstalled libreoffice, but it came back after the update). I didn’t get snapd back fortunately (though I do use Firefox packaged by Pop).

Part of the change is that Pop!_OS is moving away from ubuntu-minimal and ubuntu-standard meta packages and towards their own metapackages as shown in this this recent commit.

After the update, I simply uninstalled libreoffice… hopefully it doesn’t return in the next update :]