Silverlight is abandoned, but Winforms (especially) and WPF are mature products; I use the latter two (as well as Xamarin for Mac) in my consulting business to make good profits each year, and don't see anything changing except for better in this respect.

Yes, Silverlight has been abandoned.

I would argue that Winforms is now a mature technology and requires little upkeep, but it is still a part of the stack.

WPF development has slowed significantly, but still proceeds.

I would call Winforms and WPF "mature and maintained" rather than abandoned. Especially if compared to Silverlight.

I can provide a similar list for any big corporation, including Apple and Google.

Hm, I don't think WPF is abandoned.