You really can't blame MAT poses on backwards compatibility for everything.  There are some items on sale marked in the product requirements as needing Poser 9, Poser Pro 2010, Poser Pro 2012, Poser 10 and Poser Pro 2014, yet they include MAT Poses.  This has nothing to do with backwards compatibilty for these items. 

I don't use Dawn so I have not purchased anything for her but I am willing to bet some of the Dawn stuff on sale still has MAT Poses.

 

 

I use Poser 13 on Windows 11 - For Scene set up I use a Geekcom A5 -  Ryzen 9 5900HX, with 64 gig ram and 3 TB  storage, mini PC with final rendering done on normal sized desktop using an AMD Ryzen Threadipper 1950X CPU, Corsair Hydro H100i CPU cooler, 3XS EVGA GTX 1080i SC with 11g Ram, 4 X 16gig Corsair DDR4 Ram and a Corsair RM 100 PSU .   The desktop is in a remote location with rendering done via Queue Manager which gives me a clearer desktop and quieter computer room.