That's the whole point: to give link tracking a simple consistent interface, which makes it much easier to implement (no JavaScript libraries or proxy URLs) and to disable (a user agent can very easily choose whether to respect the ping).
> which makes it much easier to implement (no JavaScript libraries or proxy URLs)
I don't want it to be easy to implement.
> and to disable (a user agent can very easily choose whether to respect the ping).
This post is about Google working around that and just falling back to the old redirect-based click tracking for browsers that do not enable pings by default.
So having the attribute increased the browser complexity, brought no value to the user and only helped the tracking industry.
