Who said they were? Market forces will prevail in the long run.
I have read reports indicating that a record number of people are buying homes using interest only loans. Wages haven't increased appreciably to keep up with the rise in cost of the homes. And many of the homes themselves being built are just plain nuts.
There are various kinds of interest only loans. You can get an interest only conventional fixed rate loan, which has the first ten years interest only and the next 20 principle/interest. If home costs exceed the ability of people to afford them, the prices will go down. That's the way the market works.
And many of the homes themselves being built are just plain nuts.
You are entitled to your opinion. You are not required to buy them.
Market forces will prevail in the long run.
That's precisely what scares me.