Very true, even now. The professional market for WinForms is probably dead, though.

Yet ironically, I use Winforms in personal code way more today than any of Microsoft's other GUI technologies. Winforms is a great way to get a Windows app up extremely quickly that needed a simple GUI. There are plenty of ways to get a quick command line style app up, but I really don't know too many solutions that allow you to drag and drop functional GUIs as quickly as Winforms (other than VB and Delphi).

For a fully fledged app, Winforms makes no sense to me these days. But Microsoft specific syntax like WPF or UWP no longer makes that much sense to me either. Might as well spend the time on HTML+CSS+Javascript and get cross-platform support...