How many browser tabs you have open right now?

I find JavaScript and its ecosystem atrocious in many ways, but several browser tabs and Electron/WebView apps running just fine on an early 2010s PC I employ.

I don't see an XAML based C# .NET desktop app performing marginally better than an equivalent well-written Electron app either. In both cases, GPU takes care of the graphics rendering, JIT and GC do what they do, and you might be able to offload the pain points over to C++ through WebAssembly and P/Invoke or COM objects.