There's also a bevy of issues that impact programmed systems that (in theory!), don't apply to Excel. I can't guarantee the a programs output will be the same

There's also a bevy of issues that impact programmed systems that (in theory!), don't apply to Excel. I can't guarantee the a programs output will be the same after every VM patch, component update, re-deployment, or even just re-compile. Generally we have multiple devs touching the same system, or same code. Generally we want that code to be robust in the face of reuse in other components and contexts. Generally we have no ability to see production errors unless they are properly logged and monitored, etc. Worst of all I, a subject expert in nerdy things, am implementing a model in a domain I am an amateur in and have no fundamental context for assessing. A spreadsheet jockey inverts all those problems. They know what they want, and are intimately connected to its operation.