I think Michael Gartenberg nailed it at iMore:
With some products… there’s a distinct conflict between consumer understanding of the features and the value assigned to those features. While the internet was filled with a rabid fan base of customers who loved and praised TiVo at every opportunity, most consumers didn’t understand the value of a $500 “digital VCR.”
In short, if you met a TiVo owner at a party, they were rabid…. When most people tried it, the lightbulb turned on. TiVo was not an expensive VCR — it redefined watching TV. I suspect iPad is suffering from the same paradox. Customers who buy an iPad Pro understand the power it unlocks relative to a Mac. The more they use it, the more it displaces their Mac. They “get it,” but most folks just don’t.
This is the conundrum. So many people who try to use the iPad Pro to get work done just seem to have that light bulb turn on over their head. They get it. It doesn’t happen for everyone, but it happens for a lot of people. But if you don’t try it, you’ll never get it.