For instance, older characters, like Cliff's mom, seemed to get married within a week of meeting. In the one of the earliest episodes, Coach's daughter Lisa vents to her dad, "Roy is the first man that ever asked me to marry him, and I'm afraid he's going to be the last!". Her dad replies in shock, "Oh come on honey, there must have been dozens of young fellas that proposed to you!" His daughter also seems to think she should have gotten more proposals by now, and in the context of the show it doesn't seem unreasonable; Diane gets 3 within 4 years, Councilwoman Eldridge wants a proposal after dating Sam for a few months.

I don't think that was true to life at that time.

No, I was 15 to age 25 in the 80's - no one got married that fast. It was just for tv.