I have a couple of low-traffic sites ported to Hugo. They currently run from a gh-pages branch on GitHub.
Lots of things to love about this setup, deployment is a button pushed.
The only downside I found, which isn’t a big downside for me, is the fixed 10 minute cache timeout on static resources.
I could get better control with this on Amazon, but are there other reasons? It’s not about the money for me, I would be happy to chip out some money to Amazon if they could add some value.