Why isn’t the Livewire component responding to the broadcasted event even though the event is being successfully received by the browser?

It may be a namespace issue, try adding a dot prefix to the event in the getListeners() function:

public function getListeners(): array
{
        return [
        "echo:marketplace-listings,.marketplace-listing-created" => 'refreshListings',
    ];
}

as explained here: Livewire not responding to Model Broadcast Events #4831