I hate to tell you this, but the next DLC will have been started regardless of whether there are problems or not. It might only be a theme and the basics of what they want, and only on paper so far, but it will have been started, at least to that extent.
The one after that might have been started as well, at least in outline.
As for not realising they have stutter, even if it's major - surely that comes under not having it to a degree where it impacts on them, or not noticing it?
I guess my point with asking whether raising the thread *again* has any value is largely whether you think raising the thread will actually make them fix it any quicker?
Raising a collective thread immediately after a patch going "the stutter is still here for me" has value - since it is new information. Raising a thread that's essentially "yeah, you're working on it, but it's still broken like it was the day after the last patch was released" doesn't really do anything to get them to work harder or faster.
It's also not like the execs are going to be unaware of the problem, or that they've got staff working on it.
you are right, its best just not to say anything and just leave things as they are. I am sure when stellaris 2 comes out in 10 years the issue might have been resolved or not. Seeing the game still has bugs from Utopia in it (which have been acked back then) and still not fixed.
Without voicing your complaints no one will ever do something about it, even if the issue is acknowledged. In short: The more people STILL complain and point fingers at issues, the faster it will be resolved or even worked on.
If no one complains anymore, they might as well just stop working on it. As its obviously something the playerbase dont care about it.