Should dependency injector only do injections ?

injection.php

<?php

// Should injections only do injections ?

// current - "get"Instance()

$injector = new Injector(new Bindings);
// get instance by interface name
$foo = $injector->getInstance(FooInterface::class);

// "injection" only - better ???

$injector = new Injector(new Bindings);
// create instance without dependent instance
$foo = (new \ReflectionClass(Foo::class))->newInstanceWithoutConstructor(); 
// dependency injection !!
$injector->inject($foo);