I'm not convinced that the manufacturers greed level really dictates the move to shorter warranties. My guess is that it would be something that is considered "expendable" in order to try to keep the ultimate purchase price down to the consumers.
Of course this is pushed largely by the fact that a pretty big percentage of consumers have been buying the extended warranties for years now. Its easy for the manufacturer to just surmise that if the consumer wants to buy a warranty, they might as well just let someone else sell it. I have never, and will never buy an extended warranty on anything I ever buy. Only thing it gives is peace of mind at a cost. If they didn't make out well on them they wouldn't sell them so aggressively...
To a large degree I look at the warranty as being just part of marketing, a longer warranty don't make something automatically better, but it may be offered to give that appearance. Craftsman tools today are a good example, sure they will give you a free one forever, but I buy tools that don't need to be replaced. Of course for many of us here in the appliance "know" a warranty is worthless since we do our own repair work anyhow.