> steady stream of small, well-scoped items to tackle

Yes. The part of the quote parent left out is

> or the ability to close Y story points per sprint

With that in mind, it makes sense and the metric is dependent on the entire org functioning well. So to the extent it does so, this is an objective, very quantifiable, metric that all junior engineers can be compared with.

That said, this is a guide for startups. So I do believe this metric is garbaj. Junior engineers will be unfairly held to task for org dysfunction.