By contact do you mean physically seeing one another or do you just mean some sort of contact like via text, phone, Skype, or carrier pigeon?
I'm inclined to agree with you though that's only because of technology and how easy it is to stay in touch with people all day long now if you want to. You almost HAVE to intentionally not get in touch with somebody in order to pull off the silent treatement. The rub here is how much contact you think is necessary. Do you think that you need to be having full fledge deep convos every day? I'd reckon that's not necessary, serious relationship or not. I think there are days when you're not going to feel like talking much so a simple text message to say hello or something is sufficient.
I don't think that you need to see somebody every day though. Definitely not. I think the only time that's necessary is if you live together and/or are married which makes it the default position. And even then I'm sure folks would LOOOOOVE a break on occasion. Being in a serious relationship doesn't mean that there are certain rules that one must follow it just means that the commitment level is that that you two desire.
Anyway, those are my thoughts. And do you know why? Because I thoughted them. Thank you and good night.
Absence makes the heart grow fonder!
Or was it absence makes the eyes wonder?
Shoot, never could get that one straight...