Eric Wenger owns the core code to Bryce and it's also the core code for his Artmatic app.

Remember that Bryce originally was Eric's D4 stand alone app that Kia & company slapped a slick, new interface on it  and that's about all they did for Bryce1.

When Eric and Kia decided to go their  separate ways, Eric licensed his work to the Bryce franchise (not MetaCreationsor nor later Corel or DAZ).

So Open Source would require Eric's permission, which is doubtful that Eric would give since Atrmatic is one of his primary apps.

While there's no doubt that this arrangement has often hurt Bryce, it also kept it on the market (or lose the  license) and it also prevented Dan Farr from merging Bryce into Carrara, which is one if the many things he's suggested for Bryce.