Pinpoint notification not showing up on Android

Hi, I'm trying to set up some push notifications campaigns via Pinpoint, but I'm having troubles with notifications to Android.

I have both a iOS and an Android endpoint correctly subscribed. iOS works properly.

On Android, I can see push events coming through FCM (authentication is fine)^1, however, nothing is shown.

I have the impression Pinpoint is sending data messages instead of notifications^2, and using an Android service^3 to handle them as user notifications. However, our app is a Capacitor app, Cognito authentication and Pinpoint are handled as JavaScript code, so we're using Amplify JS, not Amplify Android.

If I try to send this payload, nothing is shown:

{
  "MessageConfiguration": {
    "GCMMessage": {
      "Title": "hello",
      "Body": "world"
    }
  }
}

On the other hand, this works:

{
  "MessageConfiguration": {
    "GCMMessage": {
      "RawContent": "{\"notification\":{\"title\":\"hello\",\"body\":\"world\"}}"
    }
  }
}

The problem is that Pinpoint campaigns use the former. The idea of Pinpoint would be to delegate creating campaigns to a non-technical marketing team, but we find it hard to do when one of the steps would be "prepare your message with this JSON format then stringify it" 🥲

Am I misconfiguring something? Is there a way to get Pinpoint to behave consistently between iOS and Android?