You can always reduce complexity by moving the goal posts. In context of the original proposition—that one of the core values WordPress provides is live preview—we have to assume a reasonably complex website authored by multiple people.
Live Preview means, then, that you need to:
- have a web-based editor behind secure auth,
- create an environment resembling CI to rebuild the site on demand,
- trigger rebuilds when a user modifies the content stored on the server,
- make the new build available in a draft environment
- …where it doesn't affect the live site,
- …only grant access to collaborators,
- …without breaking assets, links in the pages, CORS, or CSP.
There are more constraints and pitfalls that I'm not going to enumerate here. My point is, this stops being simple as soon as you stop being hand wavy about it.
The solution of this problem could be many, depending on the situation. I have my blog and other static sites synced to all my devices, and the server rebuilds them nightly. In most cases it makes no difference whether I’d deploy it right away, or it would be deployed within a day. Testing the website can be done completely offline, all you need is to sync your changes before the night. Triggering the rebuild on the server (which is deploy) can be done via a Shortcut from an iPhone. No way you can make it as easy with a Wordpress website.
Live Preview means, then, that you need to:
There are more constraints and pitfalls that I'm not going to enumerate here. My point is, this stops being simple as soon as you stop being hand wavy about it.