The fatal scenario for a camera vendor would be to transition your customers to DNG over some years, then a dispute arises which causes Adobe to revoke your patent license, and suddenly all your past products are in violation of Adobe's DNG patent.
You not only have to remove DNG-support on those products, but due to warranty-law in many countries have to provide an equivalent feature to the customer (--> develop a converter application again, but this time for products you already closed development for years ago).
Alternative would be to settle with Adobe to spare the cost for all that. So Adobe has all the cards in this game.
Now: Why bother transitioning your customers to DNG...?
You not only have to remove DNG-support on those products, but due to warranty-law in many countries have to provide an equivalent feature to the customer (--> develop a converter application again, but this time for products you already closed development for years ago).
Alternative would be to settle with Adobe to spare the cost for all that. So Adobe has all the cards in this game.
Now: Why bother transitioning your customers to DNG...?