Describe the bug
Server fails to load with error:
Sophisticated Backpacks (sophisticatedbackpacks) has failed to load correctly
java.lang.IllegalStateException: Failed to resolve consumer event type: net.p3pp3rf1y.sophisticatedbackpacks.common.CommonProxy$$Lambda$9379/0x0000000000000000@adb810c0

To Reproduce
Steps to reproduce the behavior:

1. Start Server
2. See error

Expected behavior
Server to start

Crash Report:
crash-2021-07-29_12.40.42-fml.txt

Versions
1.16.4-2.5.0.271

You're using OpenJ9 which is unsupported by forge because of the fact that it does things differently than other java implementations and what you're seeing here is caused by that. Switch to different Java JVM and this issue will be gone.