Lead and core contributor to Argoproj here. I agree that Tekton and Argo Workflows share a closer comparison than with Argo CD (despite the "CD" acronym appear

Lead and core contributor to Argoproj here. I agree that Tekton and Argo Workflows share a closer comparison than with Argo CD (despite the "CD" acronym appearing in the name Tekton CD). Workflows is aimed to be a more general purpose workflow engine. I like to explain workflows as a fancy Kubernetes Job object, which can be used as a building block to higher level applications. I believe the majority of workflow users are using workflows for ML, ETL, data processing pipelines. Its strength is being able to leverage your kubernetes cluster as an auto-scaling compute grid, with highly advanced scheduling capabilities (i.e. scheduling based on node attributes, pod priorities, resource requirements, etc...). That said, a fair share of users are using workflows as a lightweight CI solution, though it requires work to glue in other components to provide the complete solution (e.g. Argo Events to handle git webhooks)