Servo has always been a purely reasearch project with no intention to be ever used in production.

Not really. There's a parallel thread on the front page where everybody's talking about writing a browser engine in anything other than Rust is irresponsible, and ridiculous. And yet, no one's rushing to pick up Servo. There seem to be some projects in GTK and QT to embed it, but other than a handful of pretty niche browsers, doesn't seem like there's much use.