It's a cli wrapper. Don't know how you could say it wasn't.
edit: GSD is a cli wrapper, Superpowers not so much. Both are over-engineered for an easy problem IMHO.
No it's not. It's using Skills and Agents and runs always inside of Claude Code, Gemini CLI etc...
Both are dramatically over-engineered. & That's okay. I find them to be products of an industry reconciling how to really work with AI as well as optimize workflows around it. Similar to Gastown et al.
Otherwise, if you can own your own thinking, orchestrating, and steering of agents, you're in a more mature place.