It’s a good point, but keep in mind that’s 32 MB of code: you can cache it, but you still have to parse and initialize it for every tab. (It might not be as bad as it sounds, WASM is lighter in this aspect than JS; but it’s still a good proxy for startup performance IMO.)
It should work well for applications with longer session size, like Figma: you open a project one time and work on it for hours. I’m not sure if that’s the case with Dagger Cloud: you might be looking at a single trace, or compare dozens of builds throughout the day. The post only claims “better overall performance and lower memory usage”, but without any numbers it’s hard to tell anything.