I can respond to that.
I alluded to this earlier as well: There are two things that your amortization can do.
When you move from a 20-year to a 25-year amortization or from a 25-year to a 30-year amortization, it allows you to reduce your monthly payments on the loan. Let's say you were going to take a mortgage of $500,000. If you take a longer amortization, it will reduce your monthly payment for that mortgage.
I think you're also right that if you're a borrower and you're looking at the type of home you can qualify to purchase, taking a longer amortization could make it manageable for you to purchase a more expensive home, since it reduces your monthly payments.