Among the differences: - Silverlight was proprietary while webassembly (wasm) is open source. - Silverlight was not supported by all major browsers, wasm is. - Portions of Silverlight still live on in other technologies, and work in harmony with wasm. Most of today's fragmented JavaScript frameworks did not even exist in 2008. And you provided a supposed quote with no context. All that together pretty much makes your response worthless.