True, but there is also a bit of irony to the request in hindsight because the main thrust of the argument was that the more heterogenous the browser market was, the better it would be for web standards.

However, after Google forked WebKit Opera adopted Blink as their rendering engine, making the whole situation basically a wash in the context of the original argument.

Blink is a fork of the entire WebKit repository. The lion's share of that is WebCore (especially after removing platform bindings that don't apply to Chromium), but it's entirely fine to call it a fork of WebKit.