This lede seems kind of buried a bit but it looks like this is for creating people-centric workflows instead of yet-another-Airflow, which seems pretty cool to me.
In other words, Pneumatic ensures that each task, as part of the workflow sequence, is delivered to the user precisely when it's time for them to take action. This removes the need to constantly monitor a Kanban board and guess what needs attention.
Additionally, it creates a queue of similar tasks, enhancing focus and productivity, such as a list of phone calls to make (complete with pre-filled information) or a list of blog posts to approve.