It definitely changes the math. But in general, Americans aren't all that interest rate sensitive for this kind of purchase. Monera has no trouble finding takers for their credit card level rates. My prediction is it would take more of a hike than we've seen to have much impact.
IMO once most people have made the choice to take the big hit of finance charges, the rate doesn't move the needle that much.
30k for 10 years would break down to these monthly payments:
5% - $318.20
10% - $396.45
15% - $484
20% - $579.77
Each 5% jump equates to close to $80 - $100 more per month. By itself that's a good chunk of money. But keep in mind, there will be grocery price increases, subscription service increases, gas increases, etc. I think that will begin to impact a family's decision.
If it doesn't impact a family's decision, then the fed will keep raising interest rates until it does to slow the purchase of goods.
Now on the flip side, the family could choose to cut back on subscription services, groceries, or other spending areas to compensate for the finance costs.