I never found Nginx especially simple to setup, the config files were always messy. Caddy seems to have knocked this out of the park for me, especially considering automated https, and redirection.
I use Caddy on all my small projects right now. I haven't used it long enough to install enough faith for production sized systems yet, but hopefully I will get there because it is much easier to setup. Still, nginx is a breeze compared to apache IMO
I share your love for Caddy, but having worked with all three, I do agree that nginx is easier than Apache. The config file isn't perfect, but I wouldn't call it messy, and I prefer it's syntax httpd's. But to each their own.
Simpler than apache doesn't mean simple. As someone who sets up HTTP servers rarely, I had trouble when I tried out NGINIX.
But I suspect for people who do it more seriously, then it's nginix config hits the sweet spot. To me the language seems sophisticated, well documented and fairly well behaved if you pay attention to the rules.
That's can make it too hard for someone casually trying to quick-start some experimental project. But it's exactly what you want if you are maintaining a long-lived set up that is likely to grow and become complicated over time.