In comparison to the film, music and even newspaper industries, the publishing industry is changing rather lethargically. This does not change the inevitable fact that it will face immense changes in the future which have already been apparent for many years.
It seems like publishers have been afraid of adapting to a changing market. By analyzing other content industries they saw the pitfalls of accelerated digitalization. They tried to avoid developments such as lower prices and piracy by delaying digitalization as long as possible. Maybe they deemed the risk