What has become the case in recent elections is that the networks have grasped that election nights/mornings/weeks have become about the only time that a lot of people actually watch them live, hence why they drag things out to the extent they do. It's got little to do with 'cautiousness' or whatever.
Here's what some previous election nights would look like at about 1AM EST if the networks had their present day levels of 'cautiousness'.
I think "cautiousness" is actually a big factor; networks do NOT want to have a repeat of Florida 2000.
