Yeah, you could say that everything in Steve Jobs example could be organised by contexts. In fact, you can organise anything according to GTD by the book.
But you're missing the point.If you don't think contexts work for you then IMO you don't understand how to adapt contexts to your life. I maintain that context is a useful distinction for everyone, no matter the situation.
Steve Jobs wasn't working on unrelated projects or from context lists. He set aside a whole day to focus on some single area of responsibility, regardless of contexts, time, energy. He didn't try to fit his life into a stereotype system. Yes, could use contexts but it wouldn't be worth it. And that's my point. Organising everything by contexts is a point of friction, it takes a lot of work but it's useful only when you do cog like work, e.g. to batch process unrelated actions.