This is my experience as well. I work with AI agents a lot, they are very useful. What's not useful is some passer-by telling the AI "implement <my favorite feature>" and then sending that as a PR. I could have written a sentence to the LLM too if I wanted to, you aren't really giving me or the project any value by doing that.

Now that writing the code is the easy part, we're just going to transition to having very few contributors, who are needed for their architectural skills, product vision, reasoned thinking, etc, rather than pure code-writing.

Outside contributors have never been valuable as pure code monkeys.