Why that isn't happening - well there are many opinions as to that. Some critics of the tradition-bound law firm ethos blame its record for success. Given those earlier heady times of a seller's market, which went on until around 2007, there is reluctance to stray too far from those formulas. Others blame the mindset which has to continually consider precedents. Then there are those who complain that the powers that be at the top of the food chain want to protect what they got and so rig the system to slow down the change they recognize is inevitable.
This non-Schumpeterian mindset and behavior are increasing after Dewey & LeBoeuf imploded. It had tried to grow too fast and on borrowed money. "Gradualism" is the buzzword for the post-Dewey & LeBoeuf era.
The legal world is not the only line of business whose eyes narrow when spotting change. There are analysts, shareholders, and media who are decrying Google's continual creative destruction. They contend the company is losing its way. I take a look at Google's strategy in its volatile niches for the financial information company Motley Fool. Here you can review my thinking and connect the dots for your own law firm.