Men (or any partners/visitors) being allowed to,stay may be being used as a coverup for inadequate staffing.
the problem is, banning those visitors (of either sex) from staying overnight/outside visiting hours won't lead to a staffing increase.
My babies health was put at risk, by the inadequate staff. My dh was sent home (we didn't argue, those were the rules, after all), and I was left unable to care for my baby, amd ignored when I requested she was passed to me. When I persisted, my baby was taken away, to let me 'get some rest' and whenever I inquired as to her whereabouts afterwards, I was told to relish the peace and get some rest.
I did not want rest. I wanted my baby. I wanted support to be able to feed her, as she and I both needed. Decent equipment would have helped solve part of the issue (my bed was broken, and so lie flat only; I was post emergency c section and couldn't move). She was removed from me for hours, and only brought back when I had a virtual breakdown following a staff change the following morning. The new modwife on duty was livid at what had happened, and stayed well beyond her hours that day to help me and dd2.
None of that would have happened if I had been allowed a visitor to stay (for Dh's sake, it would have been nice if it was him, as he didn't get to see dd2 properly for a good 24 hours - once he was allowed back she had crashed and was jittery and needed to stay right next to me, but tbh, anyone wild have been of benefit).
Don't kid yourself that this kind of thing isn't still happening. Wholly inadequate care, and incompetency. But making sure visitors don't stay isn't going to magic up extra staff who are actually competent. That gap will not be plugged in a hurry. And so the only reasonable solution is to allow people,to,help the selves. In my situation, that would have meant a visitor overnight, since the staff were too busy to adequately care half the time, and downright incompetent the other half.