I don't see anything in this that bodes badly for Stackoverflow, financially or as a community.
If all the PHP questions are answered, every PHP programmer is now able to Google and find what they want to SO. That means they 1) learn that SO is the place for answers and 2) see ads.
2 years from now, when they're working in another language with less established Q&A, they'll know where to go.
"Excitement overall" really doesn't mean anything here. I don't care how much or little activity there currently is in the Objective C section because I don't use Objective C. I'm able to find the info I want and get questions answered if they're not already there. That's all that matters.
I don't see anything in it that bodes badly for Stack in terms of traffic or financially either. I never said otherwise. They're dominant and given their answer base and the value of the content, they're likely to remain so.
I believe overall stagnation in the community is guaranteed however, which is what the topic rather focuses on.
Maybe we just aren't talking about the same thing. What does "stagnation in the community" mean to you?
If it means "overall, people lose interest and stop visiting to ask and answer questions," I don't see that. I'm not visiting to fill in all the gaps in SO's content, and feeling disappointed when there aren't many gaps to fill. I'm running into questions, Googling, and hoping to find my question already answered.
If I find it and it's not answered, I'll do research and try to answer it myself. If it doesn't exist, I'll ask. If I find the answer before anyone else does, I may answer it myself.
I'm not going to stop doing that, and I don't see why anyone else will, either. What the overall trends are in the site really has no bearing on my individual participation, so it never feels "stagnant" to me.
Maybe you're imagining users who show up and surf for questions to answer, and those people are getting bored? That's just not the way I use the site, though.
If all the PHP questions are answered, every PHP programmer is now able to Google and find what they want to SO. That means they 1) learn that SO is the place for answers and 2) see ads.
2 years from now, when they're working in another language with less established Q&A, they'll know where to go.
"Excitement overall" really doesn't mean anything here. I don't care how much or little activity there currently is in the Objective C section because I don't use Objective C. I'm able to find the info I want and get questions answered if they're not already there. That's all that matters.
What's going to stop that from happening?