Seems like it's pretty equivalent? For webmentions you 1) set a header link to show where to submit mentions, it doesn't have to be the same domain afaik, and 2

Seems like it's pretty equivalent? For webmentions you 1) set a header link to show where to submit mentions, it doesn't have to be the same domain afaik, and 2) js / iframes to show the mentions from some other server. It's fine for static sites.