The article makes the argument that existing systems are easier to improve incrementally, while designing new systems is more work and not guaranteed to succeed

The article makes the argument that existing systems are easier to improve incrementally, while designing new systems is more work and not guaranteed to succeed. The problem is JavaScript-as-bytecode is not especially easy to improve. Anything you want to add/change that would make it a better bytecode has to be balanced with the language's use by humans. The solution to one-VM-to-rule-them-all is not to cram everything into a higher-level system with lots of assumptions (JavaScript) or to ignore portability (NaCl, LLVM), but to use a bytecode that's low-level enough to implement the various assumptions needed by higher layers. That way both C++ and JavaScript can run at full speed as well as have their implementations changed (even across websites!) without pushing every change through the browsers- just like native apps, with the browser providing only cross-platform and security, nothing more.