JWTs and sessions are not in any way orthogonal in a system as a whole. We use JWTs primarily for scalable backends - if a session is setup or not in the front

JWTs and sessions are not in any way orthogonal in a system as a whole. We use JWTs primarily for scalable backends - if a session is setup or not in the front end is not a concern for the API backend services. In a microservice environment there could be many of these - that’s the whole point after all. And with JWTs being sent to these they can simply verify the integrity of the caller without asking a central authority. Coupled with OAuth2 and OIDC as protocols for delegation/federation and you have a system that scales extremely well. Of course, it might not be the first concern that needs to be addressed in a small startup but that doesn’t mean it doesn’t have a place.