The purpose of the talk: to tell the JS programmers the audience how wasm code runs in different VM, how it interacts with JS and among themselves. Not the purpose: to tell how and why wasm should be used.
Dmitry will tell how wasm arranges inside on the example of Firefox and V8. How it runs, validates, compiles. Speaker believes that understanding of wasm structure will help JS programmers use or not use it for purpose and will be generally more developed. After all, wasm is the future of high-performance on the web.