Actually, the cases you described, making an investor demo or the like can be argued to be prohibited by the license! Does an investor demo or MVP count as commercial use? I’d say so. Would an MVP potentially produce data that I might use in the production of a “real” system? Likely so. Both of these are expressly prohibited by the license, straight up in the first section.
“Yeah but you’ll get away with it fine.” Will I? I also must respond to Wolfram with a record of my use within 10 days of being asked.
How is this an attractive state of affairs to build anything, even for paltry testing of an idea?