Yeah, I was one of the PNaCl naysayers. :) But wasm has different characteristics: (1) it has a forwards compatibility story because asm.js exists; (2) it's a custom IR that was designed from the ground up to not have undefined behavior; (3) it uses the Web APIs, rather than an alternate Pepper stack.
Issue (1)--the forwards compatibility story--is the tricky one. Was it necessary to have asm.js as a stepping stone, or could we have gone all the way to Web Assembly from the beginning? I don't know, and we might never know, but having asm.js around for browsers that don't support wasm certainly doesn't hurt.
Oh yeah, my post wasn't about PNaCl at all (I wasn't even thinking about PNaCl when I wrote it). It's very clear to me that wasm is a superior design compared to PNaCl, and I'm glad history went the way it did. :)
I was talking about about the sentiment that byte-code in general isn't necessary/feasible/desirable for the web.
Here are some example of the sentiment as I remember it. There was a lot of skepticism that it would be possible to design something that would be a better compilation target than JavaScript while still being fast, portable, and properly sandboxed:
Issue (1)--the forwards compatibility story--is the tricky one. Was it necessary to have asm.js as a stepping stone, or could we have gone all the way to Web Assembly from the beginning? I don't know, and we might never know, but having asm.js around for browsers that don't support wasm certainly doesn't hurt.