I have deployed a fully-fledged B2B SaaS product with authentication, multi-tenancy, real-time webhooks, three languages internationalization, all through Claude Code's loop. Skill atrophy is not an issue since I am not in competition with more experienced engineers. I am in competition with bigger teams who work slower.
The actual trap is not to write agency code, but to rely on it within a team environment where I fail to build a mental model. In a solo context, that cannot happen since the mental model will still fail for new cases, and I am the only one who can repair it.