By MATT O’BRIEN, Associated Press CAMBRIDGE, Mass. — Post a comment on Reddit, answer coding questions on Stack Overflow, edit a Wikipedia entry or share a baby photo on your public Facebook or Instagram feed and you are also helping to train the next generation of artificial intelligence. Not everyone is OK with that — especially as the same online forums where they’ve spent years contributing are increasingly flooded with AI-generated commentary mimicking what real humans might say. Some longtime users have tried to delete their past contributions or rewrite them into gibberish, but the protests haven’t had much effect.