The file format became partially open in 2008... long after Flash Player became ubiquitous, long after the format was developed and stabilized, without a standa

The file format became partially open in 2008... long after Flash Player became ubiquitous, long after the format was developed and stabilized, without a standards process (excluding ECMAScript), and without any serious attempts to write competing players (after all, Flash was already on the way out by then, plus it would have been harder to take on Flash Player's monopoly of... Flash players, than IE in its heyday). WebAssembly will have several actual competing implementations, not to mention that it's a drastically smaller addition to the existing Web platform.