sunshinestalkerr That is (almost) correct: the EA App doesn't support macOS Mojave or anything older, so when Origin is gone, EA games won't be playable on any OS older than Catalina (10.15).
What Mac do you have, and are you willing to update the OS if possible? You definitely have at least one update available, as any Mac that can run Sierra can also run High Sierra (10.13). Even though that doesn't help with the EA App issue, it does mean you haven't updated fully, so maybe there are further updates available for you.
Point is, try to update if you can, through the App Store if nowhere else. If you don't see the option, please list the full specs of your Mac: everything under About This Mac except for the serial number.