You can no longer make beacons with custom effects as of 23w31a

You can no longer give a beacon potion effects outside of the normal beacon effects using commands

Steps to Reproduce

• Build a Beacon Pyramid

• Set the Beacon to any effect

• Stand on top of the beacon

• run /data merge block ~ ~-1 ~ {primary_effect:"minecraft:darkness"}

• Notice the beacon lose its active primary effect entirely, instead of gaining darkness