They had no choice. They held off updating Poser's version of Python as long as possible, but its end of life date is 2020. As with Adobe Flash, the end is nigh. They were forced to update, and that meant breaking all the old scripts, including DSON. They did not want to do this. There's a lot of scripts besides DSON that are affected.

DAZ is the only one who can fix this, and they're clearly not interested. They haven't updated DSON in ten years. It doesn't work with any figures past Genesis 2, which suggests they really aren't getting a lot of money from Poser users. Or Poser users have figured out other ways than DSON.