I don’t think the turbo makes any difference with regards to idling. Excessive idling is generally not the best operating conditions for any engines and the owner manual warns against it, but it depends what you consider excessive idling is. Is it 20 minutes once in a while with the engine at operating temperature, is it a remote start for 15 minute in cold weather, or is it letting it run all day ? These are all very different operating conditions.
Up north, they are going with what is the lesser evil. Idling for long period of tine is bad for the engine, but so is running the engine cold or worst not be able to start it at all (most of the time being in a condition where the engine would be too cold to restart is why they let the engines running). In those conditions idling is the lesser of two bad things.
It does take some work to get these engine warmed up, but at the same time driving on a cold engine is not good due to poor lubrication of engine moving parts.
everyone above made valid points, but all in very varied scenarios. (Prevent hot spot, engine warm up, etc.). All with very different idling second order effects. Let us know what type of idling you would do and we can be more specific.