The “slow/disconnected” internet warning is now live for everyone.
It’s been tweaked so you only see the banner version if you are player in a live game that’s likely to be affected by the latency - in all other cases it’s just the discreet icon in the top right.
I just did some testing - ongoing games that I am playing in have the banner - all other pages have the discreet icon, including live games I am observing and completed games.
I have screenshots, but seems you have it figured out.