A couple of years ago a Daz3D sales rep told me that a majority of their 3rd-party sales are actually to Poser users. I don't know if this is still true. More and more of their products are geared for Genesis only, but a few have been offered for both Genesis and V4, and there are still plenty of V4 / M4 products coming out the door at Daz3D.

I dob't think they want to alienate the Poser market and the developers who make products for it. Reaching out to Poserdom is in Daz's own interest. I doubt they could survive without radically downsizing their business model if they stopped selling and supporting Poser-compatible goods.