the segmented component is not a recommended / provided component in the Cosmos design system. It is still used in a couple of places of Dev Studio ruleform but not used much at runtime in UI-Kit or Theme-Cosmos. Using a regular radiobutton is a recommended best practices when the number of choices is 3 or less.
about tabs vs accordion, we would use accordion for small articles that are related and could be expanded / collapsed. For complex UI and unrelated content, tabs is a recommended approach because they are faster to scan