Servo was a side-project. Mozilla laid off the Servo team. Its development then stopped. It eventually found a home in Linux Foundation but it lost the initial acceleration. It lost the ambition. Many key developers moved on. Whatever nature your project is, closed or open source, when you lose key people and stop training new ones, the project slowly dies. People matter much much more than the license or the parent organization.

Ladybird didn't lose its initial speed. There is a leader with strong vision. There is no shenanigans from half-assed management. There is clear and responsible funding. It attracts similarly ambitious people. All of that ends up with visible and real progress.

I've actually been watching all the Ladybird update videos (because I'm absolutely giddy at the prospect of a new, open-source browser engine), and they compare their test passing numbers to other browsers, including Servo. And from their own slides, Servo is behind them, but not by much, and making progress at about the same rate.

Maybe that says it all, considering how much of a head start Servo had, but Servo also took a very long... break, as you said.

There is a leader with a strong vision sure, but how long will he stick with it? We’ve seen him completely abandon a few projects now.