Symfony manually wiring arguments - 'arguments' vs 'bind'

bind is usually used in the _defaults section to replace any matching argument name in the services that are defined by that file.

So, taking the variables names from second example, and putting them into the more usual _defaults: stanza

_defaults:
    # autowire / autoconfig, etc
    bind:                                         #!
        $service: '@App\Service\SomeService'
        $scalar: 22

Any services that had those variable names would be replaced (unless locally overridden) with the service, or scalar value (22).