1. If every refrigerator purchased in the U.S. were made in the U.S., what would the guy who makes refrigerators for a living do once every household and office building in the country had a refrigerator?
2. The assumption that durable goods don't last as long as they used to may be correct, but you've overlooked the fact that we now replace things we used to repair. New appliances are so cheap these days that I don't even think a business that repairs household appliances is a viable commercial venture anymore.
That's like saying if new homes last as long as they used to, builders would be out of work.