Can someone clarify? WP is not only SAAS, but also packaged software. You can use WP's platform to host your blog, or run it on your own server. Wix is strict

Can someone clarify? WP is not only SAAS, but also packaged software. You can use WP's platform to host your blog, or run it on your own server. Wix is strictly SAAS, AFAIK (can I get a few more abbreviations in there?). You can only use their software on their platform - there is no packaged software that you can run on your own server. Is this a GPLv3 thing? Did they somehow plug the SAAS hole? Otherwise, it doesn't seem Mullenweg/WP has a leg to stand on.