PRISM and the Art of Not Losing Meaning
Opening — Why this matters now Generative Sequential Recommendation (GSR) is having its moment. By reframing recommendation as an autoregressive generation problem over Semantic IDs (SIDs), the field promises something long overdue: a unified retrieval-and-ranking pipeline that actually understands what items mean, not just where they sit in an embedding table. But beneath the hype sits an uncomfortable truth. Most lightweight GSR systems are quietly sabotaging themselves. They collapse their own codebooks, blur semantic boundaries, and then wonder why performance tanks—especially on sparse, long‑tail data. PRISM arrives as a sober correction to that pattern. ...