If I hadn't been hearing that the illegal immigrant population has remained unchanged at approximately 11 million _for decades_, I'd probably agree with you.
I think a lot of people are truly in denial about just how many illegal immigrants are in the country, and they all need housing.
11/330 is about 3% of the US population. No way 3% of the people are causing 30% of the price rise. Beyond that, if the number has stayed constant for decades, the market has had time to incorporate them. I stand by 30% being, if not a lie, thoroughly suspicious.
I think a lot of people are truly in denial about just how many illegal immigrants are in the country, and they all need housing.