Why would anyone do this, so their content can be easily read elsewhere potentially with a load of ads surrounding it?
This seems to really reason through only the happy path, ignoring bad actors, and there'll always be bad actors.
CORS also doesn't prevent a popular website with a personal vendetta[0] against a blogger from DDOSing the blog with their visitors, since CORS doesn't block requests from being sent.
For a purely static website, there shouldn't be any risk from enabling CORS.
The DDOS angle is unrelated? You can do that whenever you want.
The risk is other people profiting/taking credit for your work.
If all of this is true, why does anyone put a license on any software? It doesn't mean someone can't copy paste, but it gives them recourse. Enabling CORS is completely giving up any recourse you have IMHO
True, but the bad actors can defeat any security mechanism you put in place with a proxy, or a copy'n'paste, so the downside risk is pointless worrying about. The upside of allowing traffic is that your content that you presumably want people to read can be read by more people. For all but the most popular blogs that's probably a net benefit.