Open comes with the ability to participate, an open door is to let something physical through, not like a transparent window that lets one see, an open market, open auction, or open sports league explicitly implies more than just viewing the activity.

For many of us, we've never used "open" to mean viewing.

Right now I wouldn't trust the license to let me message my boss or buy something from a store on my personal phone without violation, commercial activity is an extremely broad term.