I am not sure exactly how it can be implemented, but I imagine that compiling and serving a binary file could allow for some maliscious things. My biggest worry is that many content blockers override js and search scripts for keywords and functionality which they muitigate. I could see a binary file executing code which provides pop-ups, advertisements or drm which would be harder to eliminate than it is now.
I am not 100% sure if this is true, but it seems possible.