Bug for services key in messenger.yaml ?

messenger.yaml

# Doesn't work with that

framework:
    messenger:
      transports:
        amqp: '%env(MESSENGER_TRANSPORT_DSN)%'

      routing:
        '*': amqp

services:
    App\MessageHandler\WithDelaySerializer:
      decorates: 'messenger.transport.serializer'
      arguments: ['@App\MessageHandler\WithDelaySerializer.inner']

services.yaml

# Works with that
parameters:
    locale: 'en'

services:
    _defaults:
        autowire: true      # Automatically injects dependencies in your services.
        autoconfigure: true # Automatically registers your services as commands, event subscribers, etc.
        public: false       # Allows optimizing the container by removing unused services; this also means
    App\:
        resource: '../src/*'
        exclude: '../src/{Entity,Migrations,Tests,DataFixtures/data}'
    App\Controller\:
        resource: '../src/Controller'
        tags: ['controller.service_arguments']

    App\MessageHandler\WithDelaySerializer:
      decorates: 'messenger.transport.serializer'
      arguments: ['@App\MessageHandler\WithDelaySerializer.inner']