I'll believe this when it's done. Nothing I've seen so far indicates that this would be feasible.

As a practical counterexample, the Linux kernel has a verifier for eBPF code that is loaded by untrusted users. That is a much more constrained environment than JS, but they still constantly have verifier bugs. It's so bad that distros almost universally distrust the verifier and instead set things up s.t. only root can load any eBPF code.