That article is out of date and is no longer correct for the newly released 2.3.x.
With current version of bbPress, you only files that need to be in your theme are the files you plan on changing.
For example if you want to tweak the CSS, then you would copy the bbpress/templates/default/css/bbpress.css to [your-theme-directory]/css/bbpress.css and bbPress will automatically use your version instead.
This goes for almost all the bbPress template files. For example, let’s sayo you want to edit the bbPress search page. You would copy bbpress/templates/default/bbpress/content-search.php to [your-theme-directory]/bbpress/content-search.php.
The only time you would really need to copy and create the entire bbPress template would be if you need it to be theme independent, eg distribute it.
Hopefully that makes some sense 