I set "MONSTERS" to not spawn above sea level, but then also set each individual illager as well as the "raiders" entity type to always spawn, following the example of fixing Ocelots being classified as "monsters". Hostile mobs do not spawn above sea level even at night, which is what I wanted, but now Pillagers will not spawn at all in Pillager Outposts. They do spawn in patrols however. I attached the config file as a txt file since yaml is not supported here. Is it something I did wrong, or is it something to do with how the mod/mc works?
mobfilter.txt

Hey! Same but I solved it from 1.18 to 1.20.1!
Wanted to help out as I had the same "issue" 'cause I think Minecraft puts all types of Illagers in the Monsters category, I think, but I have not found a list of mobs by category, yet

Here's a part of my modified rule I use:

• name: Always allow ocelots. Minecraft thinks they are MONSTERS.

  what: ALLOW_SPAWN

  when:

  entityId: ['minecraft:ocelot', 'minecraft:illusioner', 'minecraft:pillager', 'minecraft:evocation_fangs', 'minecraft:evoker', 'minecraft:vex', 'minecraft:vindicator', 'minecraft:slime', 'minecraft:stray', 'minecraft:allay', 'minecraft:ravager', 'minecraft.phantom', 'minecraft.bat', 'minecraft.skeleton_horse', 'minecraft.zombie_horse', 'minecraft.sniffer', 'friends&foes:mauler', 'friends&foes:glare', 'friends&foes:iceologer', 'friends&foes:copper_golem', 'friends&foes:tuff_golem', ]
  

You can ignore the Friends and Foes and, just in case Minecraft thinks those are Monsters too, I've set the Allay to be allowed to spawn, as many others.

Cheers! Hope it works, let me know!

Ah sorry I've looked at the code you sent only now haha my bad

My guess is to not repeat multiple times the "- rule:" part. So what I did is set ONE "- rule:" and then just added mob ids.

i'm slightly confused now - was this just an issue in your config? can I close this?

I think it was an issue with the way the config was written, yes
If they don't reply I guess we can close this issue?
Cheers!