Edge functions are typically run intermittently, with their runtime stopped to free up resources between runs. Therefore a big factor is startup and shutdown speed. Containers are pretty bad there. Deno is better, and WASM is unbeatable, especially with things like Wizer[0].
Deno can in theory do the pre-initialization that wizer does for JS too. We have all of the infrastructure for it, we just have not gotten around to actually implementing it yet.
Makes sense when talking about edge functions, but then OP started talking about Kubernetes. Our Kubernetes workloads don't resemble that at all; there's virtually none of that container startup/shutdown overhead to be concerned about. Most weeks, no containers are started or stopped at all.
[0]https://github.com/bytecodealliance/wizer