it depends. For dramas that are good that obviously isn't long enough. But most dramas that are not good are one hour each just because that's the norm now, not because they actually use that time wisely and/or need it. The Walking Dead for example, would spend 10 minutes recapping the last episode, then have something nice happen in the first 5 minutes, then a bunch o normally completely irrelevant bullshit would happen for half an hour then something exciting with a cliffhanger would happen in the last 10 minutes. It wasn't so bad when it started out but later on that show started to absolutely suck because they made everything an hour, even if there was nothing to tell.
Comedies on the other hand like the Office or Modern Family, are just find at 22 mins to half an hour.
I think you mentioned this before where it is slow and boring and picks up at the end making sure you tune in for the next gripping episode. Those type of shows lost me when you realise not much is actually happening.
it's a system that unfortunately works on a lot of people and this makes me upset that so much of the global population is so easily entertained to the point where I tend to look down on them and find them stupid. I don't know who figured this out for the first time but it seems to have worked it's way into almost all shows that are made these days... and I find that really lame.