Are you in the construction or related business? I've had to learn some of these things the hard way myself. I learned I was outclassed and so I hired a geotech

Are you in the construction or related business? I've had to learn some of these things the hard way myself. I learned I was outclassed and so I hired a geotechnical engineer to design my now-deployed drainage. (french drain plus site drainage) I wonder what building codes require, ie from engineering and inspection POV, like can the things you mention even be built today? If so isn't this a failure of the planning departments?