Any suggestion on minimal project structure for ASP.NET Core

Question

This screenshot below are actually from three separate classlibs API, Core, and Infrastructure. There is no right or wrong in doing whatever based on the developer's preference.

I see there are some developer separating more than 10 or 20 classlib. Maybe, they are building the next Facebook, not offending but appraising. In my case, I am doing small-medium size project like Monitoring and Reporting or CRM system.

Just curios to get some suggestion from the community.

My goals are:

1. to have very simple yet scalability and maintainability. I am confidently we do not change any technology in the future which means if I use EF Core or Dapper or ADO.Net, it will be like that forever. This project is one-off project.
2. Simple enough for less experiences developer to start / continue from once I hand-over the project source code.
3. Less and less code / saving more time not to do injection, interfaces ... which are unnecessary.