request()->validate vs $this->validate

The difference is since Laravel 5.5, the validate method is available on the Illuminate\Http\Request object (request()->validate) rather than previously via the ValidatesRequests trait that was mixed into Controllers ($this->validate).

The newer implementation also functions as a filter similar to request()->only(), returning only the request fields that are specified in the rules array. This means you need to add a key/value pair with an empty value to pass the field through

$data = request()->validate([
    'name' => 'required',
    'email' => 'required',
    'age' => ''
]);

$user = User::create($data);

If what you're saying is true then they're basically the same, because the controller method also returns only the request fields that are specified in the rules array.

Only, since 5.5 it does.