KSLC chart has outdated parking gates

Hi,
no the charts are accurate …

The yellow area is a construction area and will currently not be used (or at least partly due the constructions). The D parking gates are now stands as you see. This is also corresponding to the FAA charts and the airport map on the airport webpage.

Here from the airport webpage - you see the D stands and the missing terminal buildings:

Here are the FAA airport diagram - you see also the dotted lines (yellow):

Hope that helps
Richard