First and foremost, breathe. Everything is going to be ok!
- Best case scenario, you only have newer games which are already 64bit compatible and an upgrade to Catalina would not harm a thing.
- Worst case scenario would be that you install a prior macOS on a second partition so that you have both the newer Catalina, and the older Mojave (or Sierra) to run your older games which died in Catalina.
So you are wondering if you should Upgrade to macOS 10.15 Catalina (as your Software Update may be pressuring you into). You may first want to make considerations about the Applications you currently have and use (especially ones you wish to continue to use for awhile yet). Not only games, but all your non-Apple Applications are subject to this change.
- As with all macOS updates that break prior games in your library, Catalina is no different (except that it will break a lot more than usual). Upgrading to Catalina will cause all 32bit-only Applications to cease functioning! You will not even be able to launch them.
- Game Developers have known about this impending change for many years now, and many new Mac Games are designed with 64bit support. However not all are 64bit compatible!
- Keep in mind, the MacGameStore is a store and service that sells the games made by developers. MacGameStore does not make these games, and can not update them to 64bit without source code. When a developer provides an update to a game, we will post the updated game (if we host the download).
- Games provided through 3rd party systems (like Steam) are also under the same limitations and restrictions. Some games on those services will see updates too from their developers (but not all, especially really old games).
If you are thinking of upgrading to Catalina:
- Many games will not run!
- Pay close attention to the "64bit Support" line in the "System Requirements" area. We try our best to gather the full information from developers and publishers, however sometimes they are still unknown.
- We also have added '64bit' badges on product lists for all 10.15 users using the MacGameStore App.
- Sadly, MacGameStore can not issue refunds for older 32bit-only games you bought beyond the allowed return period. If you dual-boot anyhow, those games can still be played fine!
- If you have an older Mac that ran 10.14 (or earlier). You can still setup a dual-boot on another partition for those games (it may be daunting, but its a viable solution).
- Ultimately, upgrading to Catalina is your choice to make. Hopefully this information helps you decide.
Further information about this transition and the change from 32bit to 64bit, and other helpful documents: