I don't think you get the idea. "Building software" by itself doesn't mean anything; software is made to have some utility.
The parent is not talking about code, if you're starting a business, the industry defines a major part of what you do.
Sure your product is made to have some utility, but it doesn't have anywhere near the impact on your day to day activities that people think it does.
The industry defines a major part of what your software does, not as big a part of what you do. I think it's an important distinction.