I often hear people comparing Squarespace and Showit or sometimes Wix to WordPress. I don’t understand how they compare, but at this moment, WordPress does not compete with them.
However, I’m very optimistic that WordPress can if they want to. With block (Gutenberg) editor, WordPress should go wilder with it.
The so-called Full page editor isn’t going to cut it. It’s just a page editor after all. Provide all the template (or pattern) you want, it’s not what WYSIWYG user looking for. Even with a well-built WYSIWYG editor like Squarespace, Showit or Wix, there is still customization question from the users. So pattern alone doesn’t work.
Gutenberg editor is like a beginner type of WYSIWYG editor, with limited features which are very well thought out, at least it will not mess up the whole layout with a little scales of width.
The one and only thing WordPress now lacking is the header and footer selection/creation. At least giving a taste of a site builder, then we will see how plugins coming out.
So far, there are very limited good site/page builder plugins. All of them are bloated and required quite some technicality on optimization. So with WordPress fully submerge into site builder, perhaps plugins too will improve.