This seems to me more like another case of "death of a business model caused by revenue maximization strategy". "Open-core" does not have "non-viable" or even "must-be-bait-and-switch" stamped all over it. But if the organization using it decides that its primary goal is revenue maximization (and/or significant growth), then it becomes much more questionable how it will fare.
But isn't that the goal of any business, I hear you cry? No, it certainly is not. There are thousands of small businesses even just in the USA that are happy to work within the limitations of their situation and initial desires.
But isn't that the goal of any business, I hear you cry? No, it certainly is not. There are thousands of small businesses even just in the USA that are happy to work within the limitations of their situation and initial desires.