It's also somewhat idealistic. After all, it was only in 1920 (13 years before the essay was written) that in the US women got the right to vote. And even today in some states felons are not allowed to vote.
Edit: And of course people under 18 also don't have the right to vote.
But you have to remember that in Switzerland, the people had to vote in this. Only 12 years earlier in 1959, 2/3 of the voters voted against it. In 1971, 2/3 of the voters voted for it. A big turnaround in a short time.
Do you really think that most countries would have given women voting power when they did it if they'd asked the voting people (that is men at the time)?
When we grow up, we think the world as it is now has always been that way. Only with time we learn that lots of what we take for granted has actually been around for a very short time.
In Portugal, women got granted the same rights to vote as men only in 1976 because the country was a dictatorship until then. Hard to imagine that there were dictatorships in Europe only 40 years ago. In Spain, the other dictatorship at the time, women got the right to vote in 1931 but because of the dictatorship soon established afterwards, they couldn't vote for 40 years (of course, neither could men).