According to Sam Altman, the proposed $20 plus subscription model allows users to convert their subscription into credits usable across features such as deep research, o1, GPT-4.5, and sora. This model offers flexibility with no fixed limits per feature, empowering users to allocate credits according to their needs. If users deplete their credits, they have the option to purchase more. This approach could potentially streamline user engagement and spending efficiency (source: Sam Altman's Twitter).