Big fan of static site generators and the whole JAMStack idea in general - I use Jekyll extensively - but after building a site with Gatsby, I found it too over-engineered.
React is great, and definitely has its place, but to set up React, GraphQL and all the surrounding tooling just to assemble some text files into a template seems like complexity for the sake of it.
For me, the fun of static sites - after years of building sites with CMSs like Wordpress and Drupal - is that they’re as close as possible to plain HTML, lightning-fast and very simple.
Not only is Gatsby over-engineered, it's also bloated IMO. I think one of their main selling points it that page loads seem instant. Preloading other pages in the background seems needless to me when we're talking about a simple blog. Sure, it might be good for apps, but forcing my (few) visitors to download needless mbs on desktop or mobile seems like a bad user experience to me.