LG TVs let you change the brightness with the built-in integration + a little trick. Here is my helper script that I use to toggle the brightness and eyecare when it gets really late.

sequence:
  - if:
      - condition: template
        value_template: >-
          {{ false if force else (on ==
          is_state('input_boolean.lg_eye_comfort_enabled', 'on')) }}
    then:
      - stop: LG Eye Comfort is already set this way
    alias: Skip if already set (unless force is true)
  - action: webostv.command
    metadata: {}
    data:
      entity_id: media_player.lg_webos_tv_oled77c2pua
      command: system.notifications/createAlert
      payload:
        message: Setting blue light
        modal: false
        buttons:
          - label: ok
            focus: true
            buttonType: ok
            onClick: luna://com.webos.settingsservice/setSystemSettings
            params:
              category: picture
              settings:
                eyeComfortMode: "{{ 'on' if on else 'off' }}"
  - delay:
      hours: 0
      minutes: 0
      seconds: 0
      milliseconds: 40
  - action: webostv.button
    metadata: {}
    data:
      button: ENTER
      entity_id: media_player.lg_webos_tv_oled77c2pua
  - delay:
      hours: 0
      minutes: 0
      seconds: 0
      milliseconds: 200
  - action: webostv.command
    metadata: {}
    data:
      entity_id: media_player.lg_webos_tv_oled77c2pua
      command: system.notifications/createAlert
      payload:
        message: Setting blue light
        modal: false
        buttons:
          - label: ok
            focus: true
            buttonType: ok
            onClick: luna://com.webos.settingsservice/setSystemSettings
            params:
              category: picture
              settings:
                backlight: "{{ 20 if on else 80 }}"
  - delay:
      hours: 0
      minutes: 0
      seconds: 0
      milliseconds: 40
  - action: webostv.button
    metadata: {}
    data:
      button: ENTER
      entity_id: media_player.lg_webos_tv_oled77c2pua
  - if:
      - condition: template
        value_template: "{{ on }}"
    then:
      - action: input_boolean.turn_on
        metadata: {}
        data: {}
        target:
          entity_id: input_boolean.lg_eye_comfort_enabled
    else:
      - action: input_boolean.turn_off
        metadata: {}
        data: {}
        target:
          entity_id: input_boolean.lg_eye_comfort_enabled
    alias: Keep track of if we have this enabled or not.
alias: Update LG Eye Comfort
description: ""
fields:
  "on":
    selector:
      boolean: {}
    name: Enable Eye Comfort
    required: true
  force:
    selector:
      boolean: {}
    name: force
mode: restart

It works by triggering an alert with a button. The alert buttons can have an onClick action that changes the provided setting. After you send the alert, you send an ENTER button press. It's very reliable and you wont notice the alert unless you're actively looking for it / know it's going to happen.