i think 'onboard' might refer to the wider context of using a tool in say, a research group. it's not just you learning the tool, it's about how the group uses the tool and the historical developments in place.
It's just a tech business language mannerism. People use it for the same reasons they use "price point" instead of "price", or "usecase" instead of "use", or "form factor" instead of "size": to show that they belong to the tribe, and to sound clever while saying something that could be expressed more simply and elegantly. The jargon adds nothing, except cringe.