A few hot takes:

- Library is under the GPL 3, vastly more restrictive than most existing GUI toolkits

- WebAssembly rendering in Firefox most certainly not living up to the name. I think the slide animations on the print example are managing around 5-10 fps

- Keyboard input / control focus seems absent in the demos. This would also suggest the much more important detail of accessibility also missing

- Compiles layouts to code. Is this really necessary? Visual cortex places severe restraint on how much complexity can go into a UI. Code generation on the other hand says a lot about how painful the dev-build-debug cycle is likely to be.