find documents where array does not contain certain value

[macrozone]

consider a collection messages that has a readBy array relation to users.

 {
      name: 'readBy',
      type: 'relationship',
      relationTo: 'users',
      hasMany: true,
}

you want now show all unread messages:

both llms i asked suggested this

 const result = await payload.find({
    collection: 'messages',
    depth: 0,
    where: {
      and: [
        {
          conversation: {
            equals: conversationId,
          },
        },
        {
          readBy: {
            not_in: [userId],
          },
        },
// ...

to my surprise this doesn't work when there are more than one entry in the readBy array for a message.

There is no not_contains or nor a not operator, so there seems to be no API for this.

I am very surprised, this should be a totally basic usecase. Is there no way of doing this?