I’m well aware of hardware support for enforcing memory safety, but that’s not quite what I’m talking about here: browser plugins have historically been poorly sandboxed, while WebAssembly should be an improvement in this area.
It is really nothing new here, just the politics to have a bytecode execution platform that everyone agrees on.
For example, if I can replicate a Flash security flaw with CheerpX, should I blame Flash, CheerpX for being a good implementation, or WebAssembly for allowing Leaning Technologies to faithfully re-implement Flash?
the security model of the web site based on executing arbitrary code, so you would need to assume that the wasm you receive tagged it's memory in the most malicious way possible anyway.
the way I see it real hardware needs this kind of checks more because they have worse sandboxing