How to prevent 1P's icon from appearing in the Dock at startup

I see where some of the phrasings we used above may have given the wrong impression. I apologize for that. I'd reiterate this statement as the most accurate state for this discussion at this time:

Our design team has done some brainstorming around this, though it doesn't look like we've yet landed anywhere solid.

There are plenty of opinions about how this should work, even amongst our team members. I am making sure that we consider your position in that conversation. I cannot promise that we'll go in any particular direction here. We may ultimately decide that the current behavior is how things will continue to work.

There are very many Mac apps that start when logging in and don't display an app icon in the dock. They only show up as a small icon in the top Mac menu bar, so I don't quite understand your point or why 1P has to display an app icon in the dock.

That is correct, but in fairness: there are just as many if not more that do not work that way.

Ben