> any AI system that runs on a computer that i do not control is by my definition not Open Source.

This is not true at all. It would be open source if you could download it and run it anywhere that is capable, and are free to move it and modify it as much as you want.

Just because you don't have a computer at home powerful enough doesn't mean it isn't open source.

I think he means theoretically in possibility space, without relying on a based insider leaking a 'closed' frontier model to bittorrent or hyphanet.