I'm a huge static site fan (lookup jamstack).
What I've historically had a problem with was hosting. For public pages, it's great.
For private internal docs, it's been problematic. It's more servers and access control to manage if you want something for a specific group inside a company to access.
This new update is a big deal for those that want to provide an internal hugo, jekyll, mkdocs, or other static generate based documentation site for their team.