No users, only learners
Unless you believe that learning suddenly stops at some point, when I think about the audience of a development tool, there is never a point where someone stops being a learner.
If someone is trying to understand how to integrate Kafka with your API, they want to learn. If someone is trying to optimize their server configuration so database writes are more performant, they want to learn. If someone asks a question in your support channel, they want to learn.
The act of using or building leads to learning because it's an experience (the "user experience" of your product or the "developer experience" of your SDKs).
Sure, from a metrics and measurement perspective, it makes sense to understand when someone switches from learning about your product to using it.
But make no mistake: everyone is on a learning journey with your product. I don't see developers, buyers, builders, investors, users, customers, or decision makers – to me, it's learners all the way down [the funnel]. I'm always asking, "What do they want to learn at this point, what motivates them to want to learn it, and how do we deliver that learning to them so they're better off on the other end of it?"
Have a lovely day,
Kamran