alt Hacker NewsWin32 API is great and responsive; ATL/WTL (and MFC) are still very useful abstractions with little cost. The biggest pain point is having to handle a lot of things manually, like DPI awareness (and themed controls). Even things like Emoji and other modern text features are not available through GDI and require DirectWrite iirc. Still, I'm surprised how useful it manages to be regardless how old it is.
When you say responsive, you mean like it reacts quickly, or it responds to screen size?
In web we refer to the latter but i feel you mean the former.
I built a toy project in .NET 2005[0] with WinForms and the experience was actually excellent, binding data to controls was dead simple, it felt surprisingly modern. But i can't imagine how I'd make the UI resizable lol
[0]https://github.com/queenkjuul/spotify97