Even the most liberal Christian will acknowledge that as archaic as the staunch traditionalist view is on gay clergy, it is at least based on something explicitly stated in the bible.
The arguments against women as priests before and as bishops now are altogether more to do with interpretation and supposition. The Internet and academia are littered with essays written on this subject from both sides none of which have the direct word of Christ or God on the matter. There is the primary argument that we should follow his example and he only chose penis wavers to be fishers of men. However on that note no vicar can eat pizza, Christ didn't. Archbishop don't get on that aircraft, is is not approved by the demonstrative school of rules about following the apostolic succession.
The secondary arguments are mostly based on readings of the Epistles, the salutation to Junia (along with Andronicus) in Romans "my fellow-prisoners, who are of note among the apostles, who also were in Christ before me" Vs 1 Timothy and "Let the woman learn in silence with all subjection" with of course the attendant debates about authorship of those letters.
In any case we can but speculate about the motivations for the all boys club, so why do some people hold that there opposition to the ordination of women is a gospel truth?