Here is a step by step tutorial on how to downgrade tvOS 13 final to tvOS 12 on Apple TV HD (1080p model).
Before you move forward, please check out the following:
Download tvOS 13 Final for Apple TV 4K, Apple TV HDClean Install tvOS 13 on Apple TV [How to]
If, for some reason, you feel that tvOS 13 final is not your jam at all then you can downgrade tvOS 13 final to tvOS 12 right now as long as Apple is signing the older firmware. Remember, the downgrade window is extremely small and will likely close without prior notice. So make sure you downgrade right away if you want to stick around with tvOS 12 instead of tvOS 13. Furthermore, the downgrade will erase everything off your Apple TV so make sure you are ready to reinstall all your apps once you are done with it all.
Note: This downgrade tutorial is not applicable to Apple TV 4K since it does not have a USB-C port to interface with a PC or Mac. Also, you will requite a USB-C cable to go through the download. Make sure you have the right cable before going ahead.
1. Download the tvOS 12.4.1 firmware file from this link and save it to your desktop for easy access later on.
2. Connect your Apple TV HD with your PC or Mac using a USB-C cable.
3. Launch iTunes.
4. After a few minutes your Apple TV HD will show up in the top left hand corner of iTunes. Click on the tiny little Apple TV-like icon to reveal more details.
5. Click on the Restore Apple TV button while holding down the left Shift key (Windows) or the left Option key (macOS).
6. Select the tvOS 12 firmware file you downloaded in step 1.
7. iTunes will now extract the firmware file, restore your Apple TV and show a prompt on screen telling you that the process was successful.
The entire process should take no more than 15 minutes at best. Use the time to reflect on life and make yourself a nice cup of coffee. Please make sure that you leave your PC or Mac alone while the downgrade is in process. A slight mishap may force you to start from the beginning which you totally do not want to do.
tvOS 13 is a wonderful little upgrade that makes the Apple TV a far better set-top box compared to many out there. There is support for multiple users, Apple Arcade, Xbox and PlayStation controller support as well as brand new HDR screensavers.