Continuing the example of buying homes... wouldn't that be a good (or neutral) thing since it means we wouldn't have so many people speculating on real estate, and taking out easy loans to buy homes, leading to unhealthy increases in home prices?
I agree that the housing market is not the ideal example but we need to look at debt in general when talking about deflation. In a deflationary setting, reduced lending reduces the speed that money moves around and depresses the economy. Business have trouble closing the book because falling prices of goods sold today are not enough to cover the cost of supplies from when they were manufactured a month ago. Periods of deflation have tended to go hand in hand with major economic busts, which is why modern monetary policy tries to avoid even the mildest form of deflation.
In your example, the problem is that it is harder to take a bitcoin-denominated loan to purchase a house because your bitcoin-denominated wages go down every year and eventually you can't pay off the interest anymore.