> This proposal seems to be taking that approach to the extreme - not even a kernel.

To be fair, there is a kernel - the Go runtime. But since there is no privilege separation it classifies as a unikernel. Performance gains should be expected compared to a system where you have to copy data to/from guest VM kernel space to guest VM user space.

> I wonder if it could run on cloud VMs?

Yes. TamaGo currently runs in KVM guests with the following VMMs: Cloud Hypervisor, Firecracker microvm, QEMU microvm.

> How tiny could the image become?

Roughly the same size as your current Go binary. TamaGo doesn't add much.