Traveling down this rabbit hole myself; it's been frustrating. Thanks for sharing your detailed understanding of the AI to PSD issue.

I am creating an asset pipeline for a Unity game project. The flow is AI to PSD to Unity. Though I am considering AI to Affinity Designer to PSD to Unity since I already own Affinity Designer. But the loss of names and most groupings is a hard pill to swallow when using Affinity Designer.

PSD to Unity has its own set of somewhat similar issues but we're developing a Photoshop UXP plugin to take care of some of that.

Training Illustrators on this pipeline seems like it may be a futile effort. I am going to try out the Ai2Psd script and the SVG Layers extension as a possible solution.