Happens because of iaf refactoring some code in IaFDamageRegistry, as seen here

May require to account for more changes than that one, as this is a very large update, the last being in last year's August and this one being four days ago as i'm writting this issue.

Aren't dependendcies configured per project? Anyways good luck with the gradle or IntelliJ problems, try reverting the java version to the one you used previously or upgrade gradle if that's even possible with forge 1.16

I do see this issue, and would like to fix it, but I am having some rather annoying issues with gradle/IntelliJ.
Unable to make field private static final java.util.Map java.lang.ProcessEnvironment.theCaseInsensitiveEnvironment accessible: module java.base does not "opens java.lang" to unnamed module @35bbe5e8
I believe this is caused by an incorrect Java version/configuration, which I have due to newer versions of Minecraft using newer Java.

I seem to have this issue also with my modpack.
crash-2023-06-11_20.12.02-server.txt