I will like to hear from those in USA. At major tango cities along the west coast from Vancouver to LA/SD, I haven’t noticed higher proportion of women like being talked about here frequently. Same in NYC once I danced there long back. Some days slightly more women, some days slightly more men. Dancing at a few local milongas in Paris and Berlin, too I don’t remember registering too many followers to be called imbalance.
At crowded milongas does balance even matter unless it is very lopsided?
I tend to see more ladies "ironing" their seats, many with unhappy expressions on their faces and/or crossing their arms, than I do men, in the events that I have been to, even ones where a quick count and estimate indicated a more or less equal number of both roles, taking into account what roles I have seen people dancing of course (there is usually at least one lady leader).
I think it kind of matters, insofar as keeping people happy with the dances they're getting. But then on one end, you have people who just want to dance as much as possible, and on the other you have people who won't dance unless the music is just right and they can dance with their partner of choice. Or the few who are content with one amazing tanda, which satisfies them for the night and leaves them with a dreamy smile. So I'm unsure actually.
But people who dance one role definitely do not want to compete for a limited number of dancers in the other role, which becomes increasingly unpleasant with a greater imbalance.
Even when the roles are roughly balanced, you tend to see a (small?) group of leaders having their pick of followers and dancing whenever they want to, young/attractive and/or excellent followers dancing almost every tanda, and still plenty of ladies sitting down unless it was live music, with some visibly impatient to dance or looking around actively for leaders. Some leaders sitting/standing about. Lastly, some leaders/followers who have not found the right partner for that particular tanda at that time. We of course ignore the people who are eating, drinking, resting, socializing, or watching the floor.
If I had to give an estimate, it was probably about 10% of followers sitting down every tanda? At least, that was what I observed at an ostensibly role-balanced tango marathon.
And this is only a wild guess from observation in general, which may very well be wrong, but female followers tend to want to dance more than male leaders, ceteris paribus. I am quite possibly biased, given that I tend to observe followers' body language more than leaders' for obvious reasons.