I think you are right but I also think that's a good thing. The web is a spec so every new implementation improves it. Serenity is apparently writing it's browser to more closley follow the spec (as opposed to just producing the right outputs) which is also good. So I think Ladybird provides more improvements to the web as a whole compared to the improvments serenity brings to operating systems as a whole. That's probably why it has more sponsors.
I like ladybird, and I think it's a cool project. It's probably more short term useful, but I think serenity is the more interesting project of the two, precisely because browsers are a spec. No one likes the absolute chromium dominance and more browser engines are a good thing, but they also all do exactly the same thing. Building an operating system is a much more open ended task that has more room for innovation.
