Anna might have different definitions, but here are mine:
Basically, there is usually one (or a few) strong proponents of an idea when it's first voiced. Those proponents (or someone who picks it up) does a lot of work to explain and popularize that idea. All those people deserve credit, because sometimes other people come and take those ideas and present as basically their own / ideas they just found around.
new good ideas
Ideas that are still correct. For example, that AI safety is important and highly under-prioritized.