Autowiring is enabled in core.services.yml

Autowiring is now used for core services. core.services.yml has the following default added:

services:
  _defaults:
    autowire: true

Many explicit service arguments have been removed as the container can now infer the correct service from the constructor argument types alone.

BEFORE

services:
  asset.query_string:
    class: Drupal\Core\Asset\AssetQueryString
    arguments:
      - '@state'
      - '@datetime.time'

AFTER

services:
  asset.query_string:
    class: Drupal\Core\Asset\AssetQueryString

This is possible because of these two earlier changes, Adding support for _defaults key to the your_module.services.yml file and Core services provide aliases for autowiring.