Well, that would be like coding your bot with a notepad - what is actually possible using the WDG Automation Language (WAL), if you remember over 600 commands and their possible configurations by heart - and something that is definitely not recommended. The Studio is the tool you should be using for the actual bot logic development/testing/debugging, wouldn't you agree?
What I'm saying here, that we need to understand that BPMN is not an implementation standard. Therefore we really can not use it to create any meaningful runnable implementations, but models (skeletons) that business can easily understand and even create themselves with IBM BWL. So, the asset might bring value by giving you kind of a shortcut to start your model based implementation, but we should be aware of the limitations of this approach. That's all.