Add a "Create database" checkbox during install process

By the way, there are many support threads asking about how to create a database.

Manually create a MySQL database?
How to create MySQL database withOUT using PHPmyadmin?
Help installing phpmyadmin to create database?
WordPress installed but did not create database

So by just including this little option you can help a lot of people during setup.

Adding that option would mean that the user would have to know and enter the root password for the MySQL server. The vast majority of WordPress sites are installed on shared hosting servers, so knowing that information to be able to enter it is just out of the question.

The biggest reason for me to say it’s not a greaat idea is that normal uses would say “Hey, this says that it can’t create a database for me… help!”, and this would be re-asked 1,000’s (or more) times just because users don’t understand just what is required.

Well, now the user has to know how to create a database, that causes trouble, too.

To me containers are arriving everywhere, using MySQL with root user because
1) it’s only available internally to the container
2) every app in a container gets their own MySQL container

Maybe the option can be hidden behind a advanced setup parameter which is remembered during setup process, like https://server/wordpress/wp-admin/install.php?advanced=true

You are sort of right about containers. Containers are not meant for every-day users, they are meant for people with at least a little technical know-how. They are getting more and more prevalent, but they are still never going to replace the low-cost hosting accounts that the majority of sites are running on (at least in the near-ish future). They are also a lot more complicated for users to set up, as they are complete server/application systems. In my mind, if a user isn’t able to follow the instructions on how to create a database, then there’s no way they’ll follow any instructions on how to use a container environment to do the same thing when they won’t have any idea of what a container even is.

I’m also not convinced about your argument of MySQL running as root being OK because it’s container-ised. As long as you can guarantee that there will only ever be one application/site/system working off it, and that that system won’t ever get hacked, them OK I’ll go along with that. In the real world running anything as root for a public-facing environment is something that should be avoided at all costs. Even if it is “just the database” there’s a whole lot of damage that can be done using a compromised MySQL installation.

You’ll also see a lot of support requests on here from users using all of the currently available automatic installers that are included with most hosting accounts. When even those confuse people, anything more than that is just going to cause more confusion.

Hosting control panels such as cPanel and Plesk will, for security reasons, create database users that do not have the capability to create databases. All databases must be created from within the control panel. That is why applications such as WordPress do not have the option to create a database.