Furthermore, today's demanding professional are tomorrows Joe Schmoes: having the hearts and minds of pioneers would them better see what's coming on the horizon. It just seems silly not to invest money to keep the power-user niches happy.
They could do this, but they have yet to prove that they will do it. Ever since Jobs, Apple has been hyper fixated on focused, profitable product lines. The Pro is out of step with that, and I bet with laptops making up the bulk of their computer sales, we'll start seeing them move away from the iMac too.
My only guess right now is that they still feel they need the Pro to maintain their computer business, but I fear they are slowly becoming just a gadget company and will forget their roots.
Apple's claim is staked on high-margin products, so it needs an elite cachet much more than say... Xiaomi or Dell. And you can signal that to consumers with one-of-a-kind high-end products that operate on the absolute cutting-edge of various creative, technical, and scientific niches.