> Creating a simple window in Wayland isn't much harder than in Win32. You get a wl_surface, attach a wl_buffer to it, wrap it with xdg_toplevel and handle some callbacks for resizing etc. There's some boilerplate that allows all this to be extensible in backwards-compatible ways, but nothing complex, really. simple-touch example in Weston repository has about 400 lines.

I believe the youth nowadays calls what you wrote "copium". Because creating a simple window in Win32 (a whole program, in fact) looks like this:

    #ifndef UNICODE
    #define UNICODE
    #endif 
    
    #include <windows.h>
    
    LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam);
    
    int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PWSTR pCmdLine, int nCmdShow)
    {
        const wchar_t CLASS_NAME[]  = L"Sample Window Class";
        
        WNDCLASS wc = { };
    
        wc.lpfnWndProc   = WindowProc;
        wc.hInstance     = hInstance;
        wc.lpszClassName = CLASS_NAME;
    
        RegisterClass(&wc);
    
        HWND hwnd = CreateWindowEx(0, CLASS_NAME, L"Hello World! Program",
            WS_OVERLAPPEDWINDOW,
            CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
            NULL, NULL, hInstance, NULL);
    
        if (hwnd == NULL)
        {
            return 0;
        }
    
        ShowWindow(hwnd, nCmdShow);
    
        MSG msg = { };
        while (GetMessage(&msg, NULL, 0, 0) > 0)
        {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }
    
        return 0;
    }
    
    LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
    {
        switch (uMsg)
        {
        case WM_DESTROY:
            PostQuitMessage(0);
            return 0;
        default:
            return DefWindowProc(hwnd, uMsg, wParam, lParam);
        }
    }

That's significantly less than 400 lines, and requires essentially just two function calls, RegisterClass and CreateWindowEx, the rest is the message loop and its callback.