I think Flash died 2 years too early, or WebAssembly came 2 years too late. Because it always seemed to me that Flash was a good idea for the web, if it existed as a layer that was not "native" could be linked as a library (on top of Wasm and canvas). Alas, there were plans to emulate Flash using Wasm, but it was on its deathbed by the time we were starting the open design process. Adobe's VM seems to have had some design decisions that made it difficult to just "hit the button" and make it run decent on Wasm.