The art assets are made in a version of Spine we don't have pirated copies of. So standard movements solo just requires a call to their individual character 'scene'. Every sex scene requires both participants redrawn and a scene made just for them. These aren't 3D models being swapped, but calls to a unique scene combo. It starts to add up in work, and while yes AI could theoretically do the work. . . why? If you just wanted AI scenes to wank at, you could do that.
Look, the group here could very well animate and code faster if this was the only thing they did. Even if this was their job, no one should be slaved to a desk to produce more content for others. We collectively have very little idea of anyone else's life or the difficulties they face, or if they are facing burnout do to a variety of things. They come here on occassion and do keep tabs on the thread. Their Pixiv entry specifies them as a team of 3 as well. No idea if that is still true, but likely is.