[Jordrok]

I think you're misunderstanding. The "myth" being referred to in that third link is that it's beneficial to warm up your engine by letting it idle for a long time. This was previously true for cars with carburetors, but is no longer useful for modern cars.

The idea that idling the engine for an extended time after a cold startup can cause damage is correct, and that idea is consistent in all three articles you're referring to.