The main reason we are at a point we are is that it is possible to build very complex software systems cheaply: both the tools and building blocks are abundant and available to everyone.
If an engineer tried to build a skyscraper or a bridge, they'd meet challenges other than them having knowledge or professional certification.
And to your point, if anyone ever asked an engineer to insert another floor between 8th and 9th floor of a 15 story building, they'd laugh at them. In software engineering, this is possible even if hard.
And finally, because of software living a much different life, it will be hard to define criteria for good software.
If an engineer tried to build a skyscraper or a bridge, they'd meet challenges other than them having knowledge or professional certification.
And to your point, if anyone ever asked an engineer to insert another floor between 8th and 9th floor of a 15 story building, they'd laugh at them. In software engineering, this is possible even if hard.
And finally, because of software living a much different life, it will be hard to define criteria for good software.