Your assumption is that we use Intel's definition of a "workstation" when we define the "workstation" product is simply wrong.

Also, I think we need a modern desktop that supports hi-dpi screens, touch interface (both are going to be fairly common in laptops very soon), with modern components (systemd's logind session management, wayland instead of Xorg).

Can Mate do hi-dpi? Or wayland? Does it support multi-seat configurations out of the box? Does it have a proper support for touch-based devices?  An on-screen-keyboard? Integrated cloud services? Integrated web apps? The answer to all these questions is absolutely no.

Not to mention GNOME actually has far more people working on it and testing it - even outside fedora.

Mate is about holding back and refusing to adapt to changes. Fedora is about moving forward as quickly as possible. Mate is incompatible with that by definition, and since the "workstation" product will be the main product of Fedora, it makes no sense to put a desktop like Mate in it by default.

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