Sodium 0.6.7 breaks More Culling.
I am not sure if it's a bug or a rework of API or other, but reverting to 0.6.6 fixes the issue.

Log : https://mclo.gs/adCedxZ

This has already been fixed in the latest commit: 97364a1

Get the fixed MoreCulling JAR here:
https://github.com/FxMorin/MoreCulling/actions/runs/13212235829

Hope it'll be backported to 1.21.1

Fix was backported and released