Though I am a big Rust fan, I think Ladybird is evolving fast enough that my money is on Ladybird to become a true daily driver first. The biggest obstacle to that is JavaScript as Ladybird still uses its homegrown engine ( very slow ) and Servo is integrating SpiderMonkey.
Ladybird just got a million dollar shot in the arm. We will see what becomes of that.
Despite the Mozilla origins, I do not think you can say Servo is backed by Google. The claim from Ladybird is that it is the only browser not financially supported by Google.
I would say that Servo is corporate backed at this point and Ladybird still is not ( backed by donations only ) but with large donations by a single donor, we will see if Ladybird is able to stay completely independent over time.