Yeah, that's more or less correct.

> The new combined shader will be named "Mesh" shader

It's only new for Vulkan. On Windows and XBox, mesh shaders were implemented couple years ago: https://devblogs.microsoft.com/directx/coming-to-directx-12-...

This new Vulkan extension is a direct copy-paste of the above, leveraging the same hardware.

However, the hardware support for mesh shaders is less than ideal. That thing needs feature level 12.2, so-called "DirectX 12 Ultimate". It only works on nVidia Turing (GeForce 20 series) or newer, and AMD RDNA2 (Radeon RX 6000 series, and current generation of game consoles).