The housing developer seems to be a purely supply-side economist.
The argument that ever lowering interest rates lead to "affordable" homes is not evident in any real world data that I've looked at. Evidence points to the contrary.
Houses are always priced at what people can afford to pay for them. The median price of a house is directly linked to size of the mortgage a couple working for median wage can be cleared to loan by a bank.
5% mortgage rate? For a $200k home that's $10k per annum to cover the interest.
2% mortgage rate? That $200k home is now $500k. The devious detail here is that the time to pay off the loan changes completely.
The $200k home can be paid off in 25 years with $670/mo plus interest.
The $500k home? 62.5 years with $670/mo plus interest.
It gets even better - assume the 5% mortgage rate equals 5% inflation rate.
In a high inflation, high interest rate environment, the $200k home is devalued by 5% per annum. Assuming wages keep up with inflation, the $670/mo payment is smaller and smaller piece of the total income.
A couple earning $100k together per year spend $18k or 18% of their (pre-tax) income on their $200k home during the first year. If their income stays the same but is corrected for inflation, 25 years later their income will be $338k in inflated dollars but their mortgage payments will be $18k / $338k = 5.3% ! Eaten by inflation!
Compare this to a scenario where another couple buys a $500k home in a low interest rate, low mortgage rate environment. During the first year, their payment is equal to the other couple. After 25 years of 2% inflation/interest rates/mortgage rates assume their wages keep up with inflation as well. The couple's combined income will be $164k in inflated dollars. The mortgage payment will be 10.9% of their total income.
The "2%" couple pays over twice as much as share of their income as the "5%" couple after 25 years and the "2%" couple is expected to keep paying the loan down 2.5x longer (62.5 years vs 25 years).
This is basic high school math with nothing fancier than exponentials, so I'll leave the equations as an exercise to the reader.