Well a short response and strictly from a business standpoint for OEMs, printers aren't cheap.
Many AM companies are either small companies who are looking at purchase a few printers and start an AM shop. Many may see the extra cost to an already expensive printer, an unnecessary expense, as they aren't going straight into mass production anyways.
On the other end of the spectrum, you have fortune 500 companies, investigating AM for production, but still in the prototyping and R&D stage. PR3D wasn't really necessary when their engineers we're asking for money for prototyping and R&D.
Now, with both of those end users moving into production the story changes, however, the printers have already been sold and need to be outfitted with PR3D for these companies to hit their yield numbers.
So perhaps, over the course of 2018 when OEMs ask their customers hey how's that printer doing, they say great, have you heard of this 3dSim Flex software and this PR3D thing?
If enough end users have adopted PR3D, it then becomes a viable business model for OEMs. Until then, why would they risk trying to upsell something they aren't positive on, when they're more interested in selling just their product.