I would be very impressed with someone who's been vibecoding "a lot" for about a year who could then go back to being fully in the loop for even 50%. I would even say I'd expect withdrawal symptoms at that point.

The dopamine hits are core to why people even do vibecoding (or vibecoding-in-a-dress/spec-driven development) and why they tend to overestimate its output so much. Hell, it's core to all forms of LLM-assisted development (because it feels like magic), but most of the other forms are more value, less delusion.