MarkMLl, I think it's worth reading in full what they write. Read what is written in Hardware Enabling for Wayland.
It says /typically/, in other words that's one of the possibilities and the one that the developers are using... or were using at the time that (undated) document was written. It then goes on to describe a client-side EGL stack and so on.
The Wp page says "EGL is an interface between Khronos rendering APIs (such as OpenGL, OpenGL ES or OpenVG) and the underlying native platform windowing system."
Again, I'd emphasise the "such as" there, and would point out that OpenGL is listed as one of the possibilities with- by implication- others being potentially usable.
I don't like saying this, but in English "typically" and "such as" do not imply any sort of definite relationship. "Pi is typically assumed to be 3.14159 in calculations, and approximations such as this don't detract from the accuracy of everyday maths" is an entirely correct statement.
Sven's right, as is usually the case.
MarkMLl