The self-tooling capability is the interesting part here, not the VM persistence.
The cost/governance question is real though. I've spent 15 years in product management and the pattern is always the same: autonomous systems that compound capabilities sound great until you need to explain to someone why it did what it did.
The gap isn't "can the agent build things" — it clearly can. The gap is: did it build the thing you actually needed? And how do you verify that at scale without manually reviewing every output?
Self-modifying config is a feature when it's right and a liability when it's wrong. The interesting design question is how you build the verification layer.