[1] Specifically, no OSI-approved open source license but that's what most people equate with "open source license."
It may also be worth noting that Creative Commons put a lot of effort into trying to define noncommercial over time and wasn't able to come up with a satisfactory answer. Obviously there are cases that are clearly commercial but many others are far less clear. This was being debated over a decade ago and nothing has really changed: https://www.cnet.com/news/does-the-noncommercial-creative-co...
(A legit question. Have an upvote.)
FWIW all the supposed complex questions they ask are clear cut. Advertising on a website makes it commercial, using works in a presentation at work makes it commercial, etc., they're all clearly commercial.
A harder question might be "what if I'm not charging and am giving files away" that becomes commercial if it substantially inhibits commercial activities, for example (according to copyright caselaw I've read).
But that doesn't matter that much, was the guy making $10 a month from adsense using your work commercially (legally, yes): it doesn't matter, why bother to sue them (actual damages is going to be tiny). NC is for the company advertising with your work, or ripping off your work, etc..
NC doesn't seem that hard to define but in any situation where it would be worth you suing for tortuous infringement then it's going to be very clear -- unless someone made a lot of money, or you lost a lot of money, then ...