This "Linux-hyperfocusing" is not intended. Since Windows users already have Morrowind, MGE and MWSE, they often do not bother to contribute OpenMW at all.
Linux and Mac users do not have a good way to play Morrowind (WINE provides an unstable result, even without MGE and MWSE), so there is an only option for them - to help to develop OpenMW.
As a result, we have developers for Linux and Mac, which can make development and packaging process handy for them and which can handle OS-specific bugs, and have users to test these changes.
For Windows we lack of such developers, and when someone encounters a Windows-specific bug, in many cases we can just say that we sorry.