I use Hugo + Gitlab + Netlify (free https). I use Emacs as my development environment, and Magit (https://magit.vc) has come as a boon to me. All the git shell scripting mentioned in this post reduce to few key strokes with the help of Magit. I'm not intending to divert the topic, but couldn't help mentioning that the Magit Kickstarter [1] needs some love.
Coming back to the Hugo topic, I believe that the 3 hours is a good practical estimate for someone who has never dabbled with git/github, domain control tweaks, CNAME, etc.
So don't take that 3 hour mention as a negative, and jump right into the post. Once you have the whole setup, updating your site is a simple git commit + git push (hardly a minute -- not counting the time it takes to gather content for a new post :)).
[1]: https://www.kickstarter.com/projects/1681258897/its-magit-th...