The vast majority of farms are not in danger of urban sprawl. Farms near cities are but there is a lot of land not close.
The easy test is ask someone who has known an area for 50 years how many new houses have gone up. You might be surprised. Even in depressed areas with some reduction in population, such as some areas of Appalachia, there are many new houses in rural areas.
"there are more houses in my area, therefore there are more houses everywhere" is illogical. i wish it were true in the seattle area. also, there will always be more houses today than 50 years ago in a society with an above zero birth rate.