How in the world can 20 MPG SUVs be the answer? And no cleaner?

It depends on what question you ask. If the question is "How can we sell our big SUVs to people who want to buy green?", then hybrid SUVs might be the right answer. It isn't about making them green, efficient, better, etc. It's about making them sell.
As far as most American managers are concerned, the only question that matters is "will it sell?".