but in this case the order of events was not "awesome product that was open-sourced as-is later" but "OS product that became harder and harder to install over time"
Products get bigger and more complex over time, so "harder and harder to install, configure and manage" is somewhat normal. The money spent on free or "community" edition is very difficult to justify, so it slowly degrades with time until it becomes unusable and people move on to something else. It is part of the normal lifecycle of software.