Currently on ChickenChunks-1.19.2-2.9.4.97-universal version, ChunkLoader cannot be destroyed via pickaxe like before, so you actually need like 15 seconds to break it. Bug or should work like that?

I have exactly the same problem.
Server version 1.18.2 Arclight.
It's incredibly uncomfortable. Destruction takes exactly 30 seconds by any mining method and tool.

It would be nice to change the name of the error to a more specific one so that people can immediately understand what problem this topic refers to.