According to a report a few days ago, it seems that some developers have realized that their software was not taking advantage of the iPhone 13’s 120Hz refresh feature. This led some to think that Apple had compromised this to help save the battery, but it seems that this is not the case.
In the supporting document written on his page, Apple says all apps can take advantage of the 120Hz refresh feature in the iPhone 13, and that they just need to be logged in. This is in contrast to the iPad Pro in which the software does not need to be upgraded to use the 120Hz display, but perhaps this is probably due to the larger iPad Pro battery.
The document also outlines what manufacturers can expect from the 120Hz display, which has great refinements which means they are not always stable at 120Hz and that these are not things that manufacturers can force, so they should be aware of these ‘testing programs.
Apple has also confirmed that there is a virus that affects other animations that rely on Core Animation and that editing is on the way. For now, there is nothing that end users can do other than wait and hope that their favorite developers will change their software to take advantage of the new upgrade rates.