Interesting enough I actually agree in principle with arsenico and ken. The debug button example is a weird corner case. On pretty much every smart phone you click a green call button to make a call and click a red disconnect button to disconnect. The debug button is consistent with other toggle buttons while being the reverse of a common convention. It may have been less confusing if it was a grayed out phone when off and green when connected.

UI is hard indeed.

Similar pattern is in Safari web inspector. There's a button for disabling cache in the network tab.

It's blue when on, gray when off. The tooltip describes the completely opposite state to the one that's currently active.

The icon is the same in both state, the color means nothing (since when the blue means on?), tooltip is wrong. Bah.

I think the problem is that the "Listen for debug connections" button doesn't look like a toggle (a slider that will move back and forth). If it looks like a toggle, then showing the current state is good because the button design is saying that it will toggle away from that current state, but if it's not a toggle, the user understands button icons as signifying what will happen.