It’s great news that the source is being released, but I get the impression this essentially means the company will end active development and put the onus on the OS community for future updates.
Undoubtably true, although I would add that it hardly promotes free software as a "generally good thing" if the landscape is full of zombie projects like this, devoid of any community that makes open source what it is.
From the news it didn't seem like they are abandoning it.
That's not what GP said, and I'm not sure how you got there from them pointing out this was likely the end of development. From the community guidelines:
> Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith.
onus is a formal word for responsibility or obligation. Until recently, the authors only had a responsibility to their paying customers. Open-sourcing the product instead of abandoning it is also a responsible choice.
How far must somebody take repressibility? Lifetime of unpaid updates seems a bit much.
Let's assume some good faith in those guys too!