Drupal and Wordpress are both distributed under open source licenses.
Like any software, you can usually force it into a use case it wasn't designed for. Alfresco is no exception. But, as I mentioned, Alfresco was built for Document Management. There was a time, many years ago, when Alfresco had a WCM offering, but it was eventually abandoned. You may see references in old posts or documentation to "AVM". That was the name of the repository implementation that sat underneath their WCM offering. But it no longer exists in modern versions.
The Web Quick Start add-on module was another attempt at a very basic form of Web Content Management. The way Web Quick Start works is that you create a Share site that follows a certain folder structure, then use CMIS to query for content from a custom front-end. Like AVM before it, this has essentially been abandoned, has fallen into disrepair, and I suspect will be formally removed from the product at some point.
In my opinion, Alfresco lacks very basic functionality that would be necessary for WCM. For example:
* It lacks an extensive content modeler. Yes, you can define simple models in the UI, but it doesn't take long before you'll need to use XML to define your forms. If you do that, you'll have to use AMPs and deployments will require a restart.
* It lacks an extensive forms builder. Yes, in the content model UI you can do some basic layout of your simple content model. But if you get beyond a simple layout or you want to use anything more than basic field controls, you will have to do that work yourself using manual config and coding.
* It lacks out-of-the-box web publication workflows. It does have a workflow engine, and it ships with some out-of-the-box workflows for simple review and approval, but none of them have web publication semantics. That's up to you to develop.
* It lacks sophisticated rendition support. Yes, you can define your own renditions (multiple representations of a given piece of content) and you can define your own transformations to convert content from one format to another. But most WCM solutions I've used allow much more flexibility here. For example, Alfresco is much more about mapping transformations from one mimetype to another. In the real world, the source mimetype is going to be JSON or XML, and you're going to have N output formats. So the transformation shouldn't be mimetype based but instead should be content type based. Alfresco lacks this concept. You'd have to develop it yourself.
* It lacks a reliable way to deploy assets to the file system. Yes, it does have a "File Transfer" tool but it is rudimentary.
* It lacks front-end caching mechanisms. You'll have to add your own.
* It lacks front-end search. Yes, it has Solr built-in, but it is strongly recommended that you leave it alone. If you want to create a web-facing search for just your published content, you'll either have to roll your own using Web Scripts or, better yet, install your own Solr or Elasticsearch server and index only exactly what you want.
* The underlying repository does not support branching and snapshotting. Okay, this isn't a "basic" feature, but if you have complex collaboration requirements around your web content you're going to wish you had the ability to treat your content more like a git repo than a document management store.
Those are just a few examples. To be clear, any or all of these can be addressed through custom development. But at some point you should ask yourself why bother doing that work when there are so many freely-available systems out there that already handle it.
