I'm fairly certain this is the first project I've ever seen where the end goal is obsolescence (while not being driven by profit). And that we're actually cheering for it.
I don't because by now they should already be bug free....
That sounds excellent, but what's really going to be "removed" from normalize.css is not merely the code for resolved issues, but more importantly official support for browser version X where version X+1 fixes the issue. Because browser vendors are not in the habit of backporting fixes to old versions. They simply release a new major version. IE 11 fixes some issue? Great, but it will mean nothing as long as you have to support IE 10.
normalize.css will finally become obsolete, not when all browsers fix all their issues, but much much later, when none of the browser versions we use today are used by more than 1% of the world's population anymore.
Nevertheless, it is refreshing to see a developer plan for the obsolescence of his beloved product, even if it will take 10-20 years.