I need it now.
I’m not a designer, but I can appreciate thoughtful explanations from passionate people, and I very much enjoyed watching her walk through her thought process.
Further, I find steam to be incredibly clunky, and I’d love to see them adopt her design.
I think you’re making the classic mistake of “all users are like me”. I personally liked pretty much all of her proposed changes and agree with her that Steam’s current offering is a mess of disjointed design elements. I find the layout noisy, complicated, and hard to navigate, while her proposals all felt intuitive.