I think a concern for people who contribute on Stack Overflow is that an LLM will pollute the water with so many subtly wrong answers that the collective work of answering questions accurately will be overwhelmed by a tsunami of inaccurate LLM-generated answers, more than an army of humans can keep up with checking and debugging (or debunking).
It's nice that people are willing to create content on Stack Overflow so that Prosus NV can make advertising revenue from their free labor. But ultimately only a fool would trust answers from secondary sources like Stack Overflow, Quora, Wikipedia, Hacker News, etc. They can be useful sources to start an investigation but ultimately for anything important you still have to drill down to reliable primary sources. This has always been true, and the rise of LLMs doesn't change anything.
For what it's worth, the Stack Exchange terms of service do prohibit AI generated content. I'm not sure how they actually enforce that, and in practice as the LLMs improve it's going to be almost impossible to reliably detect.
What is even more helpful than answers on S.O. are the comments. Of course it is only to begin an investigation. But who will want to clarify properly if most of the answers are LLM garbage, too many to keep up with?
It is not simply "nice", or for internet points, to take time to answer other people's questions.
Being able to pass on knowledge is the glue of society and civilization. Cynicism about the value or reason of doing so is not a replacement for a functioning structure to educate people who want to learn or to point them in the right direction.
Not specifically Stack Overflow, but I don't think we are adapted to live in an environment where correct/useful knowledge is buried so deep in mountains of AI-generated advice which looks plausible but is in fact wrong.
