absolutely agree. Software folks, such as myself, often think that we are generally smarter than others, can figure out/learn anything, and that the software way of working is the obviously correct one. Beside the project management, which the GC is invaluable for, it is nearly impossible to know enough about building and all of the related technologies, codes, and processes to end up with a home that doesn't have at least a handful of issues, as someone who hasn't worked in the industry for many years.

If you want to build a home, try building a shed. Learn about code, how to keep out water, how to insulate, how to condition the air (if necessary). You will learn how many ways there are to achieve the "best" result, how many small skills that you will need to learn, and how many products are out there that market themselves as the best.

Building a home, even if you just plan it and oversee the build, is the equivalent of a 2-5 year software project.

My advice would be to decide the things that you absolutely must have, especially the ones that will be unique to your build and communicate why you want them to a good GC. Work with an architect, a builder, etc. Let your GC manage the network of trust necessary to get a project like this done. Or pay up and find a boutique builder that builds exactly what you want.