Just some extra detail that I think you might have been missing about the German electoral system. #1 spot doesn’t refer to the leader of the party as this comment sort of seems to imply.

Germany uses a voting system called Mixed-Member Proportional. In it, you vote for your local candidate exactly the same as you would in America or the UK—using first past the post. But then you also vote for your favourite party. And there are additional seats in the Bundestag (congress) that are not tied to a particular region, but are instead used to "top up" the total of the Bundestag so that its party representation is proportional to the wishes of the voters. So if 10% of voters want the Greens and 20% want SPD, then 20% of the seats will be SPD and 10% will be Greens. If a party wins more seats in local elections than it is owed proportionally, it gets no additional people. If it wins fewer local elections than its national party vote percentage, it gets topped up using its party list. The #1 spot on that list will be the first person elected under this system, unless they also won their local race, in which case it goes to #2 instead, etc.

MMP is a really good electoral system, and honestly it’s probably the one I would advocate for and would encourage Americans and Brits to advocate for in their respective countries. Though I would replace the party lists entirely with a "nearest loser" to eliminate the problem @LwL@lemmy.world describes. I’d also prefer IRV be used for the local part of the election, though that might be overly complicating it for some. Having those proportional top-ups means third parties not just can earn a place (which is what IRV by itself does), it actually guarantees that they will earn a place, if any sizeable number of people want them to. No more Nader ruining it for Gore; instead, Nader’s party will actually have representatives elected.

So looking back at the example they described about Germany, if we ignore local seats for the sake of simplicity, if the Greens are owed 1 seat, that seat will always be a woman. If they’re owed 2 seats, they’ll have a woman and a man. Owed 3 seats and they’ll have two women and a man. Etc.

Hope that helps.