According to the community members, there is no need to use both Settings and ServiceContext. The community members state that ServiceContext is deprecated, and Settings is the new way to add global requirements in one place. Additionally, users can work with any part of llama-index by directly passing the required items like llm and embed_model without defining Settings.
You don't have to use both. Service context is deprecated and settings is the new way to add your global requirements at one place.
Today you can work with any part of llama-index even by directly passing the required items like llm, embed_model if you don't want to define settings too