“Instead of dividing the time between one midnight and the next into 24 equal hours, they divided the time from sunrise to sunset into 12 "seasonal hours" (their actual duration depending on season), and the time from sunset to the next sunrise again in 12 "seasonal hours".”

I think that can work reasonably well close to the equator, but in Athens, the ‘hour’ already would vary from about 47 minutes to about 73 minutes. Feels too large for me for such a system to work, but that may be because I’m too accustomed to the current system.

And of course, going further North, the difference becomes very large.

Because of that, I think it wouldn’t work in large parts of the world in a society that has artificial light.

There also ‘may’ be some complications to making that change, though (would hourly wages still work, for example?)