Considering some of the people I've made wordpress sites for couldn't even figure out the wordpress interface, command line anything is a no go for a large percentage of wordpress's intended audience.
Yeah, I'm sure it'd be possible to build on top of Hugo (or many other static site generators) to build something that might be usable for the typical wp customer - but afaik none of them are that out of the box. The most likely alternative I can think of is Ghost: https://ghost.org/
But, I'm not sure how easy it is to customize along the lines that people expect from wp (Now, that could be considered a feature - but it also means it could be a hard sell to someone that just wants a wp site).
If what is needed really is a static site (a "web site"/"homepage") -- I think netlifly looks quite promising:
Actually the command line interface wasn't the deal breaker for me. I was asked to help out creating a website for a tiny organization (< 10 people). Once I found out multiple people would need to collaborate and edit the website it basically eliminated Hugo as a possibility. I suppose they could sync files via Dropbox but as I'm not a dropbox user myself I have no idea how it handles merges. Git is not really a possibility for obvious reasons.
Finally, deployment is the final hurdle. If they wanted to edit a sentence on a WordPress site it's very easy. But with something like Hugo it would be a 3 step process: Edit the file. Build the website. Deploy to your web host.
But, I'm not sure how easy it is to customize along the lines that people expect from wp (Now, that could be considered a feature - but it also means it could be a hard sell to someone that just wants a wp site).
If what is needed really is a static site (a "web site"/"homepage") -- I think netlifly looks quite promising:
https://www.netlify.com/