The world does not rely on docker for security at all, cloud providers put each tenant of container runtimes behind an additional barrier, like a VM.

Secure runtimes are a superior solution to virtualisation and separate kernels. There are only two secure runtimes in common use - for javascriot and webassembly.

The point about hardware support is very unfair - if you invest the same level of effort and hardware support into webassembly, you can also i prove its performance. Thats like compaining that electric cars suck because there are no chargers - its just infra.