Back in the day when Dad earned $10k/year and saved 30% he had the full house price in ten years ($30k), so it was much easier to have a much larger percentage as a downpayment, or in fact, not get a loan at all.

Now saving 30% a year of a $78k income means you have to save for 20 years to have the full price of the house. ($480k), so you're forced to get a loan, and likely a much bigger loan