It very much depends on the complexity and scale of your site. StackOverflow is a bit of an extreme case.

For example, if instead of having hundreds of domains serving millions of users with tons of user-generated content you're just serving static content from a single server on a small site, the entire process for you might actually be as simple as just running `certbot-auto` on the production server.

I suspect the difficulty of switching for most sites will fall somewhere between these two extremes.

Yeah, we've been working on this for about a year (not continually, but as we have time to try to work through the problems). We do use subdomains though, so that is part of the problem. We keep feeling like we are getting close, but then we run into another issue. It's like a rabbit hole that has no bottom.