Docker containers are not a way to overcome difficult installation for the kind of users deploying WordPress en masse. They're (still) often on shared hosting,

Docker containers are not a way to overcome difficult installation for the kind of users deploying WordPress en masse. They're (still) often on shared hosting, in a lot of cases, using whatever control panel their host provides, and not only don't know how to use Docker, they don't have the capability to do so on the server. Even most of the folks with a VPS aren't on board the Docker hype train just yet. (Docker is cool and all, but it's not how people outside of our bleeding edge bubble are doing things, yet.)