> If you're just going off someone mentioning they "open-sourced" their work, not checking the license, and importing that into corporate projects, then you could end up with anything and would frankly be lucky to later find a FSL or BSL rather than something in the GPL family.
You would expect to be able to run the program freely, including as part of your production services, without incurring any obligations. And under any open-source license (including GPL-family) you can, because that's part of what open-source means. Getting presented with a bill because the program turned out to be BSL and the way you were using it means you need a commercial license is absolutely a scam.
