Are you really making the argument, that a finished game getting extra content is bad?
Because Dark Souls 2 was finished, and they added content to it, then re-released it.
Most games with DLC are finished, and then the DLC is added, it'd be illogical otherwise.
The main plot of the game is done, the dev is just adding more scenes and stuff to do every now and then.
This isn't a bad thing. Why would that be a bad thing?
Ever play an early access game?
Ever watch as it stayed in development hell because the devs who were already thin in numbers, did even more "thinning" by focusing on multiple things at once instead of focusing on one thing at a time?
And finishing that thing, to move onto the next thing?
This is honestly a common and almost expected occurrence with independent creators *cough* star citizen *cough*.
Granted roundscape is not a "worst case scenario" however, to ignore it not being an example is naive.
The reason I believe it to be common with independent creators is because well, no oversight, project management, yadyada. People love "being their own boss". But the reality tends to be that people need others to schedule and focus their work.
I mean its why secretaries exist, its why project managers exist. Its why middle management in general is such a big thing.
But ya, whatever, lets just view it as "extra content".
Also you miss my point in my dark souls 2 example. Dark souls 2 SOTFS came out in what 2014? Something like that, roundscape, pretty sure it came out what 2015? There is a reason I used DS2 as my example.
Imagine if now, in 2020, we were just getting dark souls 2 DLC still, with just hints at dark souls 3. People would be rolling their eyes (me), some might even be furious. THAT is my point. The game has been out for half a decade almost, just focus all your efforts on your next work.
I would use GRR Martin and his book situation, but that wouldn't be a good example for this games case. Since like you said its finished, they just won't "finish" it and move on.
Winds of Winter is the "worst case scenario" I mentioned above, or "star citizen". Its making "progress" but its been what? 10 years? That isn't what this is, however that doesn't mean it isn't something, which it is, its DS2 if it was still getting DLC in 2020.