Windows forms was the coolest thing I’d ever seen back in 2002, and it’s still my go to for a little window with a couple buttons, but the HTML/CSS ecosystem has so blown past it in the past 15 years that even built on a terrible foundation (CSS when I want Xaml) and a terrible language (JS when I want C#), HTML/CSS still ends up looking like the right choice to me for anything really sophisticated UI/UX wise.